Materiały źródłowe

• #1 Albinism – StatPearls – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK519018/

  Albinism is a group of heritable conditions associated with decreased or absent melanin in ectoderm-derived tissues (most notably the skin, hair, and eyes), yielding a characteristic decrease in skin pigmentation. […] This activity reviews the evaluation and management of albinism and highlights the role of the interprofessional team in the recognition and management of this condition. […] Early diagnosis is most important to manage ocular symptoms and maximize visual potential, which has further ramifications on general safety and wellbeing, education, self-esteem, and cognitive development. […] Ophthalmology can help confirm the diagnosis with testing. Characteristic ocular changes (infantile nystagmus, photophobia, reduced iris pigment with transillumination, reduced retinal pigment, visualization of choroidal blood vessels on a fundoscopic exam, foveal hypoplasia, decreased visual acuity, strabismus, misrouting of optic nerves on selective VEP exam) combined with cutaneous hypopigmentation.

• #2 Albinism: Types, Symptoms & Causes

  https://my.clevelandclinic.org/health/diseases/21747-albinism

  Albinism is a genetic disorder where youre born with less melanin pigment than usual. […] To diagnose albinism, healthcare providers typically do: A physical exam. A thorough eye exam. DNA testing to determine the specific type of albinism. […] There currently isnt a treatment or cure for albinism itself (in other words, something that will make your body produce more melanin). […] Because albinism is inherited, theres no way to prevent it. […] Albinism is a lifelong condition, but its manageable and typically doesnt affect a persons lifespan.

• #3 Albinism – symptoms, diagnosis and support | healthdirect

  https://www.healthdirect.gov.au/albinism

  Albinism is a group of genetic conditions in which a person has no or very little melanin pigment in their skin, hair and eyes. […] Albinism is often obvious from a baby’s appearance when they’re born, so usually, it is diagnosed at birth. If your doctor notices signs of albinism, genetic testing can help confirm the diagnosis.

• #4 Albinism – Diagnosis and treatment – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/albinism/diagnosis-treatment/drc-20369189

  Diagnosis of albinism is based on: A physical exam that includes checking skin and hair pigmentation. A thorough eye exam. Comparison of your child’s pigmentation to that of other family members. Review of your child’s medical history, including whether there has been bleeding that doesn’t stop, frequent or large bruises, or unexpected infections. […] A specialist in vision and eye disorders called an ophthalmologist usually should do your child’s eye exam. The exam includes an assessment using tools to look at the retina and determine if there are signs of problems with eye development or function. […] Genetic testing can help determine the type of albinism and the risk of passing down the gene change to children.

• #5 Albinism

  https://www.nhs.uk/conditions/albinism/

  Albinism is usually obvious from a baby’s appearance when they’re born. Your baby’s hair, skin and eyes may be examined to look for signs of missing pigment. […] As albinism can cause a number of eye problems, your baby may be referred to an eye specialist (ophthalmologist) for tests. […] Electrodiagnostic testing is also sometimes used to help diagnose albinism. This is where small electrodes are stuck to the scalp to test the connections of the eyes to the part of the brain that controls vision.

• #6 Azthena logo with the word Azthena

  https://www.news-medical.net/health/Albinism-Diagnosis.aspx

  The diagnosis is often made at birth as the skin and hair color of the baby will be much lighter or paler than the rest of the family. The presence of light patches on the skin is a clue to the presence of albinism. A full diagnosis will include a physical examination of the baby, including comparison of the pigmentation of the child with that of the parents and other members of the family. […] As a number of vision-related problems are often associated with albinism, the doctor may need to do a detailed eye examination. The ophthalmologist will assess the baby for nystagmus, strabismus and photophobia. Electrodiagnostic testing in which small electrodes are placed on the scalp to test the connection of the brain and eyes is also sometimes conducted.

• #7 Albinism | Apollo Hospitals

  https://www.apollohospitals.com/patient-care/health-and-lifestyle/diseases-and-conditions/albinism/

  Albinism Diagnosis: An ophthalmologist or the eye specialist will diagnose albinism by conducting tests which include: […] Physical exam […] Description of the changes in the pigmentation […] Exam of eyes […] Assessment of nystagmus, strabismus, photophobia […] Comparison of the persons pigmentation with other family members.

• #8 Albinism – StatPearls – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK519018/

  Albinism is a group of heritable conditions associated with decreased or absent melanin in ectoderm-derived tissues (most notably the skin, hair, and eyes), yielding a characteristic decrease in skin pigmentation. […] This activity reviews the evaluation and management of albinism and highlights the role of the interprofessional team in the recognition and management of this condition. […] Early diagnosis is most important to manage ocular symptoms and maximize visual potential, which has further ramifications on general safety and wellbeing, education, self-esteem, and cognitive development. […] Ophthalmology can help confirm the diagnosis with testing. Characteristic ocular changes (infantile nystagmus, photophobia, reduced iris pigment with transillumination, reduced retinal pigment, visualization of choroidal blood vessels on a fundoscopic exam, foveal hypoplasia, decreased visual acuity, strabismus, misrouting of optic nerves on selective VEP exam) combined with cutaneous hypopigmentation.

• #9

  https://www.aao.org/eye-health/diseases/what-is-albinism

  To diagnose albinism, an ophthalmologist will give you a thorough eye examination. He or she will look for nystagmus, strabismus and photophobia. Any one of these conditions by itself is not necessarily a sign of albinism. An ophthalmologist will also look at the retina and iris to see if they have developed as they should. […] Albinism itself has no treatment. But some conditions that people with albinism have are treatable. Other conditions related to be albinism are manageable.

• #10

  https://www.aao.org/salud-ocular/consejos/albinism-diagnosis

  To diagnose albinism, an ophthalmologist will give you a thorough eye examination. He or she will look for nystagmus, strabismus and photophobia. An ophthalmologist will also look at the retina to see if it has developed as it should. […] Albinism itself has no treatment. […] Parents, students and teachers can work together to help a child with albinism. It’s important to consider seating, lighting and optical aids in the classroom. […] Peer support groups can help children and adults with albinism.

• #11 Albinism – StatPearls – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK519018/

  Albinism is a group of heritable conditions associated with decreased or absent melanin in ectoderm-derived tissues (most notably the skin, hair, and eyes), yielding a characteristic decrease in skin pigmentation. […] This activity reviews the evaluation and management of albinism and highlights the role of the interprofessional team in the recognition and management of this condition. […] Early diagnosis is most important to manage ocular symptoms and maximize visual potential, which has further ramifications on general safety and wellbeing, education, self-esteem, and cognitive development. […] Ophthalmology can help confirm the diagnosis with testing. Characteristic ocular changes (infantile nystagmus, photophobia, reduced iris pigment with transillumination, reduced retinal pigment, visualization of choroidal blood vessels on a fundoscopic exam, foveal hypoplasia, decreased visual acuity, strabismus, misrouting of optic nerves on selective VEP exam) combined with cutaneous hypopigmentation.

• #12 Albinism: What You Can do for Your Patients

  https://www.reviewofophthalmology.com/article/albinism-what-you-can-do-for-your-patients

  OCA is most often clinically diagnosed based on the features of ocular hypopigmentation (iris and retina), skin and hair, in conjunction with decreased visual acuity. […] It is important to remember that not all children with OCA will have the snow white hair and translucent irises that may first come to mind; there is a range of light blonde to brown hair and eye color can be blue, brown or hazel. […] Therefore, albinism should be considered in the differential of any child who presents with chronic nystagmus and a fair complexion. […] Iris transillumination defects (TIDs) are another common sign of OCA and may help make the initial diagnosis. […] Macular hypoplasia is the most significant cause of decreased visual acuity in albinism. […] Best corrected visual acuity varies greatly among individuals with OCA.

• #13 Albinism

  https://www.nhs.uk/conditions/albinism/

  Albinism is usually obvious from a baby’s appearance when they’re born. Your baby’s hair, skin and eyes may be examined to look for signs of missing pigment. […] As albinism can cause a number of eye problems, your baby may be referred to an eye specialist (ophthalmologist) for tests. […] Electrodiagnostic testing is also sometimes used to help diagnose albinism. This is where small electrodes are stuck to the scalp to test the connections of the eyes to the part of the brain that controls vision.

• #14 Albinism Workup: Laboratory Studies, Imaging Studies, Other Tests

  https://emedicine.medscape.com/article/1200472-workup

  Handheld ultra-high-resolution spectral-domain optical coherence tomography (SD-OCT) is the gold standard to diagnose foveal hypoplasia and can be used in young children with nystagmus and other ocular problems to classify foveal abnormalities and help determine the cause of the infantile nystagmus with the use of foveal morphology. […] Sweep visual-evoked potential (VEP) testing is useful for predicting recognition acuity in children with albinism. Predictability was seen in a clinical spectrum of albinism. […] Pattern-appearance VEP has shown a strong association between the extent of the interhemispheric latency asymmetry and the clinical signs of albinism. This association also exists for flash VEP. […] Histologic examination of the skin of male patients with this condition and female carriers of OA1 reveals the presence of macromelanosomes.

• #15 Albinism: Symptoms, Causes, Diagnosis & Treatment

  https://www.webmd.com/skin-problems-and-treatments/what-is-albinism

  Albinism is often obvious in newborns. A genetic test can confirm it. Your doctor probably will compare your babys skin and hair to those of family members. An eye doctor, or ophthalmologist, may run a test called an electroretinography to check for vision problems linked to albinism.

• #16 Information Bulletin – What is Albinism? – National Organization for Albinism and Hypopigmentation

  https://albinism.org/information-bulletin-what-is-albinism/

  Albinism is an inherited genetic condition that reduces the amount of melanin pigment formed in the skin, hair and/or eyes. […] The presence of these eye problems defines the diagnosis of albinism. […] DNA tests can determine the precise type of albinism. […] For parents who have had a child with albinism previously, and if that affected child has had a confirmed diagnosis by DNA analysis, there is a way to test in subsequent pregnancies to see if the fetus has albinism. […] For specific information and genetic testing, seek the advice of a qualified geneticist or genetic counselor.

• #17 Albinism: MedlinePlus Medical EncyclopediaLock

  https://medlineplus.gov/ency/article/001479.htm

  Albinism is a lack of melanin production. Melanin is a natural substance in the body that gives color to your hair, skin, and iris of the eye. […] Genetic testing offers the most accurate way to diagnose the specific type of albinism. Such testing is helpful if you have a family history of albinism. It is also useful for certain groups of people who are known to get the disease. […] Your health care provider may also diagnose the condition based on the appearance of your skin, hair, and eyes. An eye doctor called an ophthalmologist may perform an electroretinogram. This is a test that can reveal vision problems related to albinism. A test called a visual evoked potentials test can be very useful when the diagnosis is uncertain.

• #18 Albinism Workup: Laboratory Studies, Imaging Studies, Other Tests

  https://emedicine.medscape.com/article/1200472-workup

  Handheld ultra-high-resolution spectral-domain optical coherence tomography (SD-OCT) is the gold standard to diagnose foveal hypoplasia and can be used in young children with nystagmus and other ocular problems to classify foveal abnormalities and help determine the cause of the infantile nystagmus with the use of foveal morphology. […] Sweep visual-evoked potential (VEP) testing is useful for predicting recognition acuity in children with albinism. Predictability was seen in a clinical spectrum of albinism. […] Pattern-appearance VEP has shown a strong association between the extent of the interhemispheric latency asymmetry and the clinical signs of albinism. This association also exists for flash VEP. […] Histologic examination of the skin of male patients with this condition and female carriers of OA1 reveals the presence of macromelanosomes.

• #19 Ocular and oculocutaneous albinism | OPTH

  https://www.dovepress.com/ophthalmological-manifestations-of-oculocutaneous-and-ocular-albinism–peer-reviewed-fulltext-article-OPTH

  Albinism describes a heterogeneous group of genetically determined disorders characterized by disrupted synthesis of melanin and a range of developmental ocular abnormalities. […] The role of visual electrophysiology in the detection of chiasmal dysfunction and visual pathway misrouting is emphasized, highlighting how age-associated changes in visual evoked potential (VEP) test results must be considered to enable accurate diagnosis, and illustrated further by the inclusion of novel VEP data in genetically confirmed cases. […] Visual electrophysiology can play an important role in the detection of visual pathway misrouting, helping to determine the diagnosis, particularly if the phenotype is mild or sub-clinical. […] The discriminant feature of albinism is misrouting of optic nerve fibres with an excess of decussating fibres at the chiasm, typically revealed using visual electrophysiology and of particular value if the clinical features are equivocal or absent, or if ophthalmic examination is difficult, eg, in young children.

• #20 Albinism Information | Mount Sinai – New York

  https://www.mountsinai.org/health-library/diseases-conditions/albinism

  Albinism is a lack of melanin production. Melanin is a natural substance in the body that gives color to your hair, skin, and iris of the eye. […] Albinism occurs when one of several genetic changes makes the body unable to produce or distribute melanin. […] Genetic testing offers the most accurate way to diagnose the specific type of albinism. Such testing is helpful if you have a family history of albinism. It is also useful for certain groups of people who are known to get the disease. […] Your health care provider may also diagnose the condition based on the appearance of your skin, hair, and eyes. An eye doctor called an ophthalmologist may perform an electroretinogram. This is a test that can reveal vision problems related to albinism. A test called a visual evoked potentials test can be very useful when the diagnosis is uncertain.

• #21 Albinism: Causes, Types, Pictures, Symptoms, and More

  https://www.healthline.com/health/albinism

  The most accurate way to diagnose albinism is through genetic testing to detect defective genes related to albinism. […] Less accurate ways of detecting albinism include an evaluation of symptoms by a doctor or an electroretinogram test. This test measures the response of the light-sensitive cells in the eyes to reveal eye problems associated with albinism.

• #22 Albinism NGS Panel | Fulgent Genetics

  https://www.fulgentgenetics.com/albinism

  Albinism refers to a group of inherited disorders that result in the absence of pigmentation (color) from the skin, hair, and/or eyes. In addition to these physical features, albinism can also cause vision impairment such as light sensitivity, poor depth perception, and legal blindness. These symptoms are typically present at birth. […] This panel may be appropriate for individuals of any age with a personal and/or family history of albinism or pigmentary abnormalities. Individuals and families who want to know more about their specific type of albinism and the chances of passing it to offspring can benefit from this test. […] Genetic testing for Albinism can: Establish or confirm the appropriate diagnosis, Identify risks for additional related symptoms, Result in more personalized treatment and symptom management, Differentiate between isolated and syndromic forms of albinism, Inform family members about their own risk factors, Connect patients to relevant resources support, Provide options for family planning.

• #23 Oculocutaneous Albinism and Ocular Albinism Overview – GeneReviews® – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK590568/

  The purpose of this overview is to: […] Review the differential diagnosis of oculocutaneous albinism and ocular albinism with a focus on genetic conditions; […] Provide an evaluation strategy to identify the genetic cause of oculocutaneous albinism or ocular albinism in a proband (when possible); […] Establishing a specific genetic cause of oculocutaneous albinism (OCA) or ocular albinism (OA) in a proband: […] Usually involves a medical history, physical examination, laboratory testing, family history, and genomic/genetic testing; […] Molecular genetic testing approaches can include a combination of targeted testing (multigene panel and chromosomal microarray to detect recurrent deletions) and comprehensive genomic testing (exome sequencing or genome sequencing). […] Genetic counseling is the process of providing individuals and families with information on the nature, mode(s) of inheritance, and implications of genetic disorders to help them make informed medical and personal decisions.

• #24 Ocular albinism: Symptoms, causes, diagnosis, and management

  https://www.medicalnewstoday.com/articles/ocular-albinism

  Ocular albinism is a genetic condition that involves the eyes. This condition reduces the pigmentation of the iris the colored part of the eye and the retina, causing vision problems. […] This article will review ocular albinism, its causes, how doctors diagnose this disorder, and the treatment and management options available for people with this condition. […] Diagnosis often starts with doctors reviewing the medical history of the person reporting ocular albinism-related symptoms and performing eye tests. Eye tests can help detect any atypical retina pigmentation or other signs relating to ocular albinism. […] If the doctor suspects ocular albinism, they may recommend genetic testing. This can help assess any changes in the GPR143 or other genes. A GPR143 gene mutation confirms the diagnosis. […] Genetic tests can detect mutations in about 90% of males with ocular albinism.

• #25 Invitae Oculocutaneous Albinism Panel | Test catalog | Invitae

  https://www.invitae.com/us/providers/test-catalog/test-434348

  The Invitae Oculocutaneous Albinism Panel analyzes genes that are associated with syndromic and nonsyndromic forms of oculocutaneous albinism which is characterized by hypopigmentation of the hair, skin, and eyes. […] Genetic testing of these genes may confirm a diagnosis and help guide treatment and management decisions. […] Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS). […] Based on validation study results, this assay achieves 99% analytical sensitivity and specificity for single nucleotide variants, insertions and deletions 15bp in length, and exon-level deletions and duplications.

• #26 Oculocutaneous Albinism and Ocular Albinism Overview – GeneReviews® – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK590568/

  The purpose of this overview is to: […] Review the differential diagnosis of oculocutaneous albinism and ocular albinism with a focus on genetic conditions; […] Provide an evaluation strategy to identify the genetic cause of oculocutaneous albinism or ocular albinism in a proband (when possible); […] Establishing a specific genetic cause of oculocutaneous albinism (OCA) or ocular albinism (OA) in a proband: […] Usually involves a medical history, physical examination, laboratory testing, family history, and genomic/genetic testing; […] Molecular genetic testing approaches can include a combination of targeted testing (multigene panel and chromosomal microarray to detect recurrent deletions) and comprehensive genomic testing (exome sequencing or genome sequencing). […] Genetic counseling is the process of providing individuals and families with information on the nature, mode(s) of inheritance, and implications of genetic disorders to help them make informed medical and personal decisions.

• #27 Functional Characterization of Splice Variants in the Diagnosis of Albinism

  https://www.mdpi.com/1422-0067/25/16/8657

  Functional Characterization of Splice Variants in the Diagnosis of Albinism […] The molecular analysis of exonic sequences of these genes allows for about a 70% diagnostic rate. […] Analysis of the exonic and directly flanking intronic sequences allows diagnosis for about 70% of patients. […] This prompted us to actively search for and characterize the second variant in patients heterozygous for a single class 4 or 5 variant. […] We describe here the identification of exonic and deep intronic variants for which various algorithms predicted an effect on RNA splicing and which were tested functionally by either reverse-transcription PCR or a minigene assay. […] The functional tests presented here allowed establishing the diagnosis of albinism in eight patients. […] This study shows that searching for non-coding variants and testing those, as well as exonic ones (synonymous, missense), for an effect on RNA splicing is warranted in order to increase the diagnostic rate in patients with albinism. […] We recommend that entire genes are analyzed in order to be able to search for deep intronic variants altering RNA splicing.

• #28 Oculocutaneous albinism: MedlinePlus GeneticsLock

  https://medlineplus.gov/genetics/condition/oculocutaneous-albinism/

  Oculocutaneous albinism is a group of conditions that affect the color of (pigmentation) of the skin, hair, and eyes. […] Researchers have identified multiple types of oculocutaneous albinism, which are distinguished by their specific skin, hair, and eye color changes, and by their genetic cause. […] Oculocutaneous albinism can result from variants (also known as mutations) in several genes, including TYR, OCA2, TYRP1, and SLC45A2. […] The genes associated with oculocutaneous albinism are involved in producing a pigment called melanin, which is the substance that gives skin, hair, and eyes their color. […] This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell must have a variant to cause the disorder. […] Genetic Testing Registry: Oculocutaneous albinism type 1A

• #29 Oculocutaneous albinism: MedlinePlus GeneticsLock

  https://medlineplus.gov/genetics/condition/oculocutaneous-albinism/

  Genetic Testing Registry: Oculocutaneous albinism type 2 […] Genetic Testing Registry: Oculocutaneous albinism type 3 […] Genetic Testing Registry: Oculocutaneous albinism type 4 […] Genetic Testing Registry: Oculocutaneous albinism type 5 […] Genetic Testing Registry: Oculocutaneous albinism type 6 […] Genetic Testing Registry: Oculocutaneous albinism type 7 […] Genetic Testing Registry: Oculocutaneous albinism type 8 […] Genetic Testing Registry: Tyrosinase-positive oculocutaneous albinism.

• #30 Albinism: Background, Pathophysiology, Epidemiology

  https://emedicine.medscape.com/article/1200472-overview

  The term albinism originates from the word, albus (Latin for white), and it is an inherited disorder characterized by reduced pigmentation. Albinism is caused by pathogenic variants in genes important for melanin synthesis. […] This genetically heterogeneous disorder is characterized by hypopigmentation of the eyes, skin, and hair. Traditionally, albinism has been classified according to clinical phenotype, and the two main categories are oculocutaneous albinism (OCA) and ocular albinism (OA). […] Thus, an ophthalmologist plays an important role in diagnosing this condition. Albinism can present as a syndromic condition, such as Hermansky-Pudlak syndrome (HPS) or Chediak-Higashi syndrome (CHS), and this should not be forgotten as it has implications in patients care and management. […] Nevertheless, in the past it was known that albinism is an autosomal recessive genetically heterogeneous disorder; however, since progress has been made in the genetics/genomics era, an autosomal dominant form of albinism has been reported.

• #31 FAQs | Ocular Albinism (OA) and Oculocutaneous Albinism (OCA) | The Vision of Children Foundation

  https://www.visionofchildren.org/what-is-ocular-albinism-faqs

  Human albinism can be divided broadly into two types, Oculocutaneous Albinism (OCA) and Ocular Albinism (OA), where oculo means eye and cutaneous means skin. […] Historically, ocular albinism is an inherited disorder in which the eyes are deficient in the amount of melanin, which gives the eye its color or pigment, while the skin and hair appear normal or near normal in coloration. […] Ocular albinism (OA) results from the inability of the normal pigment cells in the eyes (especially the iris and the retinal pigment epithelium) to produce normal amounts of pigment. […] The population frequency of ocular albinism is unknown. […] The features of ocular albinism include: reduced visual acuity (typically from approximately 20/30 to approximately 20/400); nystagmus (an uncontrollable, pendular, rapid movement of the eyes back and forth); strabismus (a muscle imbalance of the eyes in which the eyes are crossed rather than straight and parallel); and sensitivity to bright light.

• #32 Albinism – EyeWiki

  https://eyewiki.org/Albinism

  Albinism represents a set of inherited conditions characterized by absent or decreased tissue melanin in conjunction with characteristic ocular and visual pathway anomalies. Proper ophthalmic and dermatologic management may be crucial in maximizing visual potential and overall prognosis. Genetic counseling for the affected individuals and their families is recommended. […] Albinism refers to reduced pigmentation compared to others of the same racial background, with characteristic eye involvement. […] A medical exam to evaluate for the presence of a systemic syndrome is warranted in high-risk populations or when a history of bleeding, easy bruising, or previous bacterial infections is uncovered. […] An early eye examination is required to detect large refractive errors and to facilitate early diagnosis and management of amblyopia. […] As with other heritable conditions, genetic testing and counseling support may offer invaluable support for families faced with this condition. […] Diagnostic methods include molecular analysis of OA1 gene (GPR143), family pedigree analysis, and examination of the carrier mother.

• #33 Albinism – StatPearls – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK519018/

  Molecular genetic testing can confirm the diagnosis but is not routinely done. It is expensive and best done using multigene or comprehensive genome sequencing. Clinical diagnosis, especially incorporating a complete ophthalmologic exam, is sufficient. […] There is no substitute for lifelong sun protection in albinism, and the importance cannot be overestimated. […] Lifelong, periodic skin examinations (once to twice per year) with dermatology for early detection and treatment of skin cancers. […] Albinism is a relatively common genetic disorder which affects many organ systems. Thus, the disorder is best managed by an interprofessional team.

• #34 Albinism Workup: Laboratory Studies, Imaging Studies, Other Tests

  https://emedicine.medscape.com/article/1200472-workup

  In the past, hair bulb assays helped to indicate the status of tyrosinase activity. Hair bulbs are taken from the scalp, and the catalytic activity of tyrosinase is determined either by incubation in DOPA and consequential induction of melanin determined by visual inspection or by a radioactive biochemical assay in which the samples are incubated with a radiolabeled tyrosine precursor and the amount of radiolabel released after enzymatic conversion quantified spectrophotometrically. The usefulness of this test is debatable because a negative result indicates oculocutaneous albinism OCA1A, but a positive result still leaves the possibility of OCA1B, OCA2, OCA3, or OA1. […] The most definitive test in determining the albinism type is genetic testing. […] A bleeding time should be obtained in patients with albinisms prior to undergoing surgery. Some physicians recommend obtaining a bleeding time in all individuals with albinism. If HPS is suspected, bleeding time, platelet aggregation, and platelet electron microscopy is necessary. If CHS is suspected, a hematologist should evaluate polymorphonuclear leukocyte function.

• #35 How can we Diagnose Albinism?

  https://www.medindia.net/health/conditions/how-can-we-diagnose-albinism.htm

  Albinism can be diagnosed merely by observation of major or total absence of pigmentation of the skin, hair and eyes. […] Genetic testing is the most accurate way to diagnose albinism and its specific type. This is helpful in families with albinism and is useful for specific, isolated populations who carry the trait in them. […] An ophthalmologist should perform a complete examination of the eye of an affected individual. An electroretinogram test should be done to determine vision problems in albinism. […] Chemical testing of hair also provides an easy confirmation of the diagnosis of albinism. […] Recently, a blood test has been developed that can identify carriers of the gene for some types of albinism. […] Amniocentesis and chorionic villus sampling can also diagnose some types of albinism in pregnancy.

• #36 Albinism – symptoms, Definition, Description, Demographics, Causes and symptoms, Diagnosis, Treatment

  http://www.healthofchildren.com/A/Albinism.html

  It is not always easy to diagnose the exact type of albinism a person has. […] In the early 2000s, a blood test has been developed that can identify carriers of the gene for some types of albinism; a similar test during amniocentesis can diagnose some types of albinism in an unborn child. […] A chorionic villus sampling test during the fifth week of pregnancy may also reveal some types of albinism. […] There are also two tests available that can identify two types of the condition. […] The hairbulb pigmentation test is used to identify carriers by incubating a piece of the person’s hair in a solution of tyrosine, a substance in food which the body uses to make melanin. […] The tyrosinase test is more precise than the hair-bulb pigmentation test. It measures the rate at which hair converts the amino acid tyrosine into another chemical (3,4-dihydroxyphenylalanine, or DOPA), which is then made into pigment.

• #37 Albinism Workup: Laboratory Studies, Imaging Studies, Other Tests

  https://emedicine.medscape.com/article/1200472-workup

  In the past, hair bulb assays helped to indicate the status of tyrosinase activity. Hair bulbs are taken from the scalp, and the catalytic activity of tyrosinase is determined either by incubation in DOPA and consequential induction of melanin determined by visual inspection or by a radioactive biochemical assay in which the samples are incubated with a radiolabeled tyrosine precursor and the amount of radiolabel released after enzymatic conversion quantified spectrophotometrically. The usefulness of this test is debatable because a negative result indicates oculocutaneous albinism OCA1A, but a positive result still leaves the possibility of OCA1B, OCA2, OCA3, or OA1. […] The most definitive test in determining the albinism type is genetic testing. […] A bleeding time should be obtained in patients with albinisms prior to undergoing surgery. Some physicians recommend obtaining a bleeding time in all individuals with albinism. If HPS is suspected, bleeding time, platelet aggregation, and platelet electron microscopy is necessary. If CHS is suspected, a hematologist should evaluate polymorphonuclear leukocyte function.

• #38 Albinism | Doctor

  https://patient.info/doctor/albinism-pro

  Diagnosis is based on careful history of pigment development and an examination of the skin, hair and eyes. The only type of albinism that has white hair at birth is OCA1. […] Genetic testing will determine the specific type of albinism in an individual. The test is useful only for families that contain individuals with albinism and it cannot be performed practically as a screening test for the general population. Not all of the mutations that cause albinism and can be detected. […] Optical coherence tomography can be a useful adjunct in cases of OCA which display atypical features.

• #39 Prenatal diagnosis and carrier detection of albinism | Genetics in Medicine

  https://www.nature.com/articles/gim199919

  Oculocutaneus Albinism Type I (OCA I) comprises several phenotypes of hypopigmentation and low vision, caused by lack of tyrosinase activity, which results from homozygosity or compound heterozygosity of the defective autosomal recessive tyrosinase gene (TYR). […] Prenatal diagnosis of OCA I can be achieved by light and electron microscopic examination of melanogenesis in fetal scalp biopsies or by molecular genetic tests. […] The identification of the two mutated copies of TYR is achieved either by direct screening for mutations or by a combination of mutation detection and haplotype analysis, following the identification of only one mutation. […] We describe our experience in prenatal diagnosis of OCA I in families, with absolute and relative indications, using the histologic and molecular strategies.

• #40 Prenatal diagnosis and carrier detection of albinism | Genetics in Medicine

  https://www.nature.com/articles/gim199919

  During the last ten years we performed 36 tests and diagnosed 7 albino and 29 normal fetuses. […] 31 prenatal tests were done by fetal scalp biopsies using the histological approach. […] During the last 16 months we have performed 5 molecular genetic tests on DNA extracted from CVS or amniocytes, based on our population screen. […] Based on our findings, prenatal molecular diagnosis of OCA I becomes possible in an increasing number of Israeli albino families.

• #41 Ocular Albinism & Hermansky-Pudlak Syndrome NGS Panel – Greenwood Genetic Center

  https://ggc.org/test-finder-item/ocular-albinism-hermansky-pudlak-syndrome-sequencing-panel

  This panel of 18 genes is intended for patients with a diagnosis or clinical suspicion of Ocular Albinism Hermansky-Pudlak Syndrome and is performed by Next Generation Sequencing (NGS). […] Molecular testing is useful to confirm the diagnosis and to identify the disease causing mutations within a family to allow for carrier testing and prenatal diagnosis. […] If the pathogenic mutation(s) are identified in an affected individual using this panel, prenatal diagnosis is available for future pregnancies.

• #42 What Is Oculocutaneous Albinism?

  https://www.icliniq.com/articles/skin-care/oculocutaneous-albinism

  Oculocutaneous albinism is diagnosed by the clinical findings of hypopigmentation found on hair, skin, and eyes when a patient contacts the doctor. […] In addition, molecular genetic testing is necessary to find which type of oculocutaneous albinism the person has. […] Prenatal diagnosis is possible if there is an affected person in the family. […] Usually, oculocutaneous albinism is diagnosed in the newborn.

• #43 Albinism Workup: Laboratory Studies, Imaging Studies, Other Tests

  https://emedicine.medscape.com/article/1200472-workup

  Handheld ultra-high-resolution spectral-domain optical coherence tomography (SD-OCT) is the gold standard to diagnose foveal hypoplasia and can be used in young children with nystagmus and other ocular problems to classify foveal abnormalities and help determine the cause of the infantile nystagmus with the use of foveal morphology. […] Sweep visual-evoked potential (VEP) testing is useful for predicting recognition acuity in children with albinism. Predictability was seen in a clinical spectrum of albinism. […] Pattern-appearance VEP has shown a strong association between the extent of the interhemispheric latency asymmetry and the clinical signs of albinism. This association also exists for flash VEP. […] Histologic examination of the skin of male patients with this condition and female carriers of OA1 reveals the presence of macromelanosomes.

• #44 Albinism Workup: Laboratory Studies, Imaging Studies, Other Tests

  https://emedicine.medscape.com/article/1200472-workup

  Handheld ultra-high-resolution spectral-domain optical coherence tomography (SD-OCT) is the gold standard to diagnose foveal hypoplasia and can be used in young children with nystagmus and other ocular problems to classify foveal abnormalities and help determine the cause of the infantile nystagmus with the use of foveal morphology. […] Sweep visual-evoked potential (VEP) testing is useful for predicting recognition acuity in children with albinism. Predictability was seen in a clinical spectrum of albinism. […] Pattern-appearance VEP has shown a strong association between the extent of the interhemispheric latency asymmetry and the clinical signs of albinism. This association also exists for flash VEP. […] Histologic examination of the skin of male patients with this condition and female carriers of OA1 reveals the presence of macromelanosomes.

• #45 Oculocutaneous Albinism and Ocular Albinism Overview – GeneReviews® – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK590568/

  The purpose of this overview is to: […] Review the differential diagnosis of oculocutaneous albinism and ocular albinism with a focus on genetic conditions; […] Provide an evaluation strategy to identify the genetic cause of oculocutaneous albinism or ocular albinism in a proband (when possible); […] Establishing a specific genetic cause of oculocutaneous albinism (OCA) or ocular albinism (OA) in a proband: […] Usually involves a medical history, physical examination, laboratory testing, family history, and genomic/genetic testing; […] Molecular genetic testing approaches can include a combination of targeted testing (multigene panel and chromosomal microarray to detect recurrent deletions) and comprehensive genomic testing (exome sequencing or genome sequencing). […] Genetic counseling is the process of providing individuals and families with information on the nature, mode(s) of inheritance, and implications of genetic disorders to help them make informed medical and personal decisions.

• #46 Albinism: Background, Pathophysiology, Epidemiology

  https://emedicine.medscape.com/article/1200472-overview

  The presence of melanin during ocular development is important. The fovea fails to develop properly if melanin is absent during development. […] The development of the ocular system is highly dependent on the presence of melanin. […] Patients with albinism have a normal lifespan but there is an increased risk for skin cancer, and preventive measures are recommended for UV exposure. Genetic counseling is recommended for patients with albinism. […] The main goals of patient education are to determine which type of albinism is present; to exclude systemic syndromes (eg, HPS, CHS); to avoid excess sun exposure; and to provide genetic counseling for the family.

• #47 Oculocutaneous Albinism and Ocular Albinism Overview – GeneReviews® – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK590568/

  Nonsyndromic oculocutaneous albinism (OCA) caused by pathogenic variants in TYR, OCA2, TYRP1, SLC45A2, SLC24A5, LRMDA (C10orf11), or DCT (TYRP2) is inherited in an autosomal recessive manner. […] Ocular albinism (OA) caused by pathogenic variants in GPR143 (OA1) is inherited in an X-linked manner. […] If an individual has a specific syndrome associated with OCA (e.g., Hermansky-Pudlak syndrome or Chediak-Higashi syndrome), genetic counseling for that condition is indicated.

• #48 Ocular Albinism: What It Is, Causes, Symptoms & Prognosis

  https://my.clevelandclinic.org/health/diseases/ocular-albinism

  Ocular albinism is a genetic condition that can affect your eye color and your vision. But it doesnt affect your skin and hair color like other types of albinism, so its often harder to detect and diagnose. […] Ocular albinism is a rare genetic condition that others might not be able to tell you have. But its common for this condition to affect how you see the world around you. […] A healthcare provider or eye care specialist may suspect ocular albinism because of visible differences they can see during an eye exam. They can then use a combination of methods to confirm and diagnose OA, including the specific type and subtype you have. […] Ocular albinism is a genetic disorder, which means it happens because of differences in your DNA and isnt treatable. But the effects of OA on your eyes like refractive errors or eye misalignments are usually treatable. […] Ocular albinism is a lifelong condition, but its often an invisible one. Many people dont know they have OA until they undergo an eye exam that detects changes inside their eyes.

• #49 Albinism: What You Can do for Your Patients

  https://www.reviewofophthalmology.com/article/albinism-what-you-can-do-for-your-patients

  OCA is most often clinically diagnosed based on the features of ocular hypopigmentation (iris and retina), skin and hair, in conjunction with decreased visual acuity. […] It is important to remember that not all children with OCA will have the snow white hair and translucent irises that may first come to mind; there is a range of light blonde to brown hair and eye color can be blue, brown or hazel. […] Therefore, albinism should be considered in the differential of any child who presents with chronic nystagmus and a fair complexion. […] Iris transillumination defects (TIDs) are another common sign of OCA and may help make the initial diagnosis. […] Macular hypoplasia is the most significant cause of decreased visual acuity in albinism. […] Best corrected visual acuity varies greatly among individuals with OCA.

• #50 Albinism: modern molecular diagnosis | British Journal of Ophthalmology

  https://bjo.bmj.com/content/82/2/189

  Albinism is no longer a clinical diagnosis. The past classification of albinism was predicated on phenotypic expression, but now molecular biology has defined the condition more accurately. With recent advances in molecular research, it is possible to diagnose many of the various albinism conditions on the basis of genetic causation. […] This article seeks to review the current state of knowledge of albinism and associated disorders of hypopigmentation. […] Each condition of albinism is due to a genetic mutation on a different chromosome. […] Pleiotropy is exhibited by all types of albinism; single gene mutations have effects on different organ systems. […] Three major mechanisms exist by which mutations exert their effect on the pigmentation process.

• #51 Functional Characterization of Splice Variants in the Diagnosis of Albinism

  https://www.mdpi.com/1422-0067/25/16/8657

  Functional Characterization of Splice Variants in the Diagnosis of Albinism […] The molecular analysis of exonic sequences of these genes allows for about a 70% diagnostic rate. […] Analysis of the exonic and directly flanking intronic sequences allows diagnosis for about 70% of patients. […] This prompted us to actively search for and characterize the second variant in patients heterozygous for a single class 4 or 5 variant. […] We describe here the identification of exonic and deep intronic variants for which various algorithms predicted an effect on RNA splicing and which were tested functionally by either reverse-transcription PCR or a minigene assay. […] The functional tests presented here allowed establishing the diagnosis of albinism in eight patients. […] This study shows that searching for non-coding variants and testing those, as well as exonic ones (synonymous, missense), for an effect on RNA splicing is warranted in order to increase the diagnostic rate in patients with albinism. […] We recommend that entire genes are analyzed in order to be able to search for deep intronic variants altering RNA splicing.

• #52 Molecular diagnosis of albinism (2018-03-14) – EGA European Genome-Phenome Archive

  https://ega-archive.org/datasets/EGAD00001004039

  Albinism is genetically heterogeneous rare genetic condition affecting 1:17000 in the Western world (but more frequent in Africa) whose main feature is a profound visual impairment, characterised by foveal hypoplasia, abnormal chiasmatic connections, nystagmus and photofobia. […] Most hospitals will only diagnose the most frequent cases using traditional Sanger, MLPA approaches. Some will use CGH arrays. We aim to diagnose all cases of albinism through the Albinochip proposal, which combines a Sequenom first step of known mutations combined with subsequent NGS approaches. […] In some cases we fail to find a second mutation, these are good candidates for further full exome analyses.

• #53 Albinism – StatPearls – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK519018/

  Albinism is a group of heritable conditions associated with decreased or absent melanin in ectoderm-derived tissues (most notably the skin, hair, and eyes), yielding a characteristic decrease in skin pigmentation. […] This activity reviews the evaluation and management of albinism and highlights the role of the interprofessional team in the recognition and management of this condition. […] Early diagnosis is most important to manage ocular symptoms and maximize visual potential, which has further ramifications on general safety and wellbeing, education, self-esteem, and cognitive development. […] Ophthalmology can help confirm the diagnosis with testing. Characteristic ocular changes (infantile nystagmus, photophobia, reduced iris pigment with transillumination, reduced retinal pigment, visualization of choroidal blood vessels on a fundoscopic exam, foveal hypoplasia, decreased visual acuity, strabismus, misrouting of optic nerves on selective VEP exam) combined with cutaneous hypopigmentation.

• #54 Diagnosis of Albinism – Mental Matters

  https://mentalmatters.co.za/diagnosis-of-albinism/

  Albinism is usually diagnosed at birth or in early childhood, as the signs are often visible. A baby born with noticeably lighter skin. White or light blond hair, and pale eyes compared to siblings or parents may raise concerns that prompt further investigation. […] A physical examination by a doctor will assess skin and hair pigmentation and look for visual signs such as involuntary eye movements or sensitivity to light. The eyes often give the clearest diagnostic clue. Hereby, a lack of melanin in the retina and abnormal optic nerve development can be detected through an eye exam. […] In some cases, genetic testing may be recommended. This is especially useful in identifying the type of albinism and ruling out syndromic forms like Hermansky-Pudlak Syndrome. Which may require additional medical monitoring. Genetic testing can also assist with family planning decisions. […] Early diagnosis allows for intervention, including regular vision assessments, referral to low-vision specialists, and sun safety education.

• #55 Symptoms and Causes of Oculocutaneous Albinism

  https://www.verywellhealth.com/oculocutaneous-albinism-overview-4588609

  OCA can be diagnosed by conducting a series of tests and exams including the following: […] Since other conditions may have similar signs and symptoms, your healthcare provider may request additional testing before making a diagnosis. […] Ocular albinism is a disorder that affects the pigment cells of the eyes. […] At this time, there is no cure for OCA, but there are several measures that can be taken to improve visual function and protect the skin from sun damage. […] Treatment for OCA focuses on protecting the skin from the sun and correcting eye and vision abnormalities. […] Make sure to get an annual eye exam by an ophthalmologist. […] The use of sunscreens with a high SPF is key.

• #56 Albinism: Causes, Symptoms, Diagnosis, Treatment, and Prevention

  https://www.everydayhealth.com/genetic-diseases/albinism/

  Albinism is a rare genetic condition marked by little to none of the pigment melanin, which is responsible for the color in hair, skin, and the irises of the eyes. […] Albinisms effects on skin, hair, and eye color may be evident at birth, allowing healthcare providers to diagnose the condition early. […] To diagnose albinism, your provider will look for telltale signs of it with a physical exam and thorough eye exam. An ophthalmologist will also inspect your retina for signs of abnormal development. […] Diagnosis of albinism typically includes a review of your medical and symptom history. This important step helps rule out or suggest genetic syndromes like Hermansky-Pudlak and Chediak-Higashi syndromes. […] Your provider may also order genetic tests, which are the most accurate diagnostic tool for albinism and the only way to determine what specific type of albinism you have.

• #57 What Is Albinism?

  https://www.icliniq.com/articles/genetic-disorders/albinism

  Albinism is typically an inherited disorder that is characterized by minimal or no production of the pigment melanin. […] Albinism is mostly diagnosed based on the appearance of the skin, hair, and eyes. An electroretinogram is performed to diagnose eye problems related to albinism. Genetic testing is the most accurate way to determine albinism and is most useful for people with a family history of albinism.

• #58 Oculocutaneous albinism | Orphanet Journal of Rare Diseases | Full Text

  https://ojrd.biomedcentral.com/articles/10.1186/1750-1172-2-43

  Oculocutaneous albinism (OCA) is a group of inherited disorders of melanin biosynthesis characterized by a generalized reduction in pigmentation of hair, skin and eyes. […] Diagnosis is based on clinical findings of hypopigmentation of the skin and hair, in addition to the characteristic ocular symptoms. […] Due to the clinical overlap between the OCA forms, molecular diagnosis is necessary to establish the gene defect and OCA subtype. […] Molecular genetic testing of TYR and OCA2 is available on a clinical basis, while, at present, analysis of TYRP1 and MATP is on research basis only. […] The diagnosis of OCA is based on clinical findings of hypopigmentation of the skin and hair, in addition to the characteristic ocular symptoms. […] However, due to the clinical overlap between the OCA subtypes, molecular diagnosis is necessary in order to establish the gene defect and thus the OCA subtype. […] Molecular genetic testing of TYR and OCA2 are available on a clinical basis, while at present, analysis of TYRP1 and MATP is on research basis only.

• #59 Albinism – Dermatologic Disorders – Merck Manual Professional Edition

  https://www.merckmanuals.com/professional/dermatologic-disorders/pigmentation-disorders/albinism

  Oculocutaneous albinism is an inherited defect in melanin formation that causes diffuse hypopigmentation of the skin, hair, and eyes. […] Diagnosis of oculocutaneous albinism is usually obvious from the skin examination, but ocular evaluation is necessary. […] Diagnosis of all types of OCA and OA is based on examination of the skin and eyes. Early ocular examination may detect iris translucency, reduced retinal pigmentation, foveal hypoplasia, reduced visual acuity, strabismus, and nystagmus. […] Because it may not always be possible to distinguish the subtypes of OCA, genetic testing may be helpful. […] Examine the eyes and skin to make the diagnosis.

• #60 Albinism FAQs – Vision for Tomorrow

  https://visionfortomorrow.org/albinism/albinism-faqs/

  Albinism can typically be diagnosed with a simple eye exam by an experienced ophthalmologist. They look for decreased amount of pigment in the retina, foveal hypoplasia and trans-illumination defects of the iris. If the diagnosis is in question, a VEP can be used to rule out albinism. Genetic testing also can be performed. Although it is not yet perfected, it can sometimes help to identify the type of albinism and the genetic changes present. For more information on genetic testing, contact a qualified genetic counselor. […] All people with albinism, regardless of type, have one feature in common. They all have abnormal crossing of their optic nerve at the optic chiasm. With appropriate testing, the visual pathway of someone with albinism will show up as a distinct pattern on a VEP. If this pattern is not seen, one can safely rule out albinism as a diagnosis.

• #61 Albinism: modern molecular diagnosis | British Journal of Ophthalmology

  https://bjo.bmj.com/content/82/2/189.short

  Albinism is no longer a clinical diagnosis. The past classification of albinism was predicated on phenotypic expression, but now molecular biology has defined the condition more accurately. […] With recent advances in molecular research, it is possible to diagnose many of the various albinism conditions on the basis of genetic causation. […] This article seeks to review the current state of knowledge of albinism and associated disorders of hypopigmentation.

• #62 Ocular and oculocutaneous albinism | OPTH

  https://www.dovepress.com/ophthalmological-manifestations-of-oculocutaneous-and-ocular-albinism–peer-reviewed-fulltext-article-OPTH

  Evidence of albino visual pathway misrouting on VEP testing requires age-appropriate use of both flash and pattern onset-offset (appearance-disappearance) stimulation. […] The sensitivity of VEPs in the detection of albino misrouting has been estimated to be about 80%, although typical VEP abnormalities can occur in the absence of classical clinical features and the diagnosis of albinism is usually also informed by medical and family history, and detailed ophthalmic evaluation.

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