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healthfinder.gov — National Organization for Albinism and Hypopigmentation - NOAH
The National Organization for Albinism and Hypopigmentation (NOAH) was founded in 1982 for the benefit of individuals and families with Albinism and hypopigmentation. NOAH provides information and support, promotes public and professional education, and encourages research and research funding that will lead to improved diagnosis and treatment. The Organization has local chapters in some areas, and contact people in most states.. NOAH is a nonprofit group, which receives its funding through membership fees, donations, and grants. NOAH conducts national and regional conferences.
Oculocutaneous albinism - Genetics Home Reference
The four types of oculocutaneous Albinism are designated as type 1 (OCA1) through type 4 (OCA4). Oculocutaneous Albinism type 1 is characterized by white hair, very pale skin, and light-colored irises. Type 2 is typically less severe than type 1; the skin is usually a creamy white color and hair may be light yellow, blond, or light brown. Type 3 includes a form of Albinism called rufous oculocutaneous Albinism, which usually affects dark-skinned people. Affected individuals have reddish-brown skin, ginger or red hair, and hazel or brown irises. Type 3 is often associated with milder vision abnormalities than the other forms of oculocutaneous Albinism. Type 4 has signs and symptoms similar to those seen with type 2. Because their features overlap, the four types of oculocutaneous Albinism are most accurately distinguished by their genetic cause.
Ocular albinism - Genetics Home Reference
Ocular Albinism type 1 is inherited in an X-linked pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the GPR143 gene in each cell is sufficient to cause the characteristic features of ocular Albinism. Because females have two copies of the X chromosome, women with only one copy of a GPR143 mutation in each cell usually do not experience vision loss or other significant eye abnormalities. They may have mild changes in retinal pigmentation that can be detected during an eye examination.
Albinism
Answer: Albinism, or the absence of coloration, in humans is usually due to the absence of melanin pigments. This is usually due to the absence of an enzyme called tyrosinase. Tyrosinase is needed to convert tyrosine to a compound called DOPA, which is eventually converted into melanin pigments. Tyrosinase-negative Albinism is inherited as a recessive trait. Source: Mange and Mange, Genetics: Human Aspects (1980). Brian Schwartz
Ocular Albinism, X-Linked -- GeneReviews -- NCBI Bookshelf
Aberrant optic pathway projections consisting of an excessive crossing of the retino-striate fibers in the optic chiasm; i.e., the visual input from the right eye is almost exclusively directed towards the left hemisphere and vice-versa [ Schmitz et al 2003 , Lauronen et al 2005 ]. This 'misrouting' can be demonstrated in specialized laboratories by a suitable VEP technique adapted for use in clinical practice [ Soong et al 2000 , Hoffmann et al 2005 ]. Lateral placement of recording electrodes over the occipital area allows for the detection of interhemispheric asymmetries in amplitude following monocular stimulation with a pattern-onset grating. Rather than the typical near-equal response from each hemisphere, the response amplitude is disproportionately larger in the hemisphere contralateral to the stimulated eye. Some authors contend that this VEP technique is a highly sensitive indicator of Albinism [ Sjostrom et al 2001 ].
Albinism Genes
Christine Ticknor Ph.D. student Yale University New Haven, Connecticut ======================================================== Albinism is a widely distributed genetic variation..."wrong" is an inappropriate word probably. In flowers some "albino" forms are the norm and the colored specimens are the variants. In animals the opposite is usually the case. In humans I am not sure what the change in the gene sequence is but I would guess it might be a frame shift....but that is just a guess.
Definition of albinism - NCI Dictionary of Cancer Terms
A group of genetic conditions marked by little or none of the pigment melanin in the skin, hair, and/ or eyes. People with Albinism may have vision problems and white or yellow hair; reddish, violet, blue or brown eyes; and pale skin.
healthfinder.gov - Albinism
Many people ask if the incidence of Albinism in non-whites is higher than in whites. The answer is no. This bulletin discusses African-Americans with Albinism, including physical differences and copin ... Details >
MedlinePlus
Medical Encyclopedia: Albinism
Another type of albism, called ocular Albinism type 1 (OA1), affects only the eyes. The person's skin and eye colors are usually in the normal range. However, an eye exam will show that there is no coloring in the back of the eye (retina).
albinism
Albinism
Energy Citations Database (ECD) - - Document #134767
Tyrosinase-positive oculocutaneous Albinism (ty-pos OCA) occurs with a prevalence of 1 in 3900 among Southern African (SA) blacks. The major contributors to morbidity and mortality are skin cancer and decreased visual acuity. Two distinct phenotypes occur, namely individuals with ephelides (darkly pigmented patches) and those without. There is complete concordance with regard to ephelus status among siblings. The disorder is linked to markers on chromosome 15q11.2-q12, and no obligatory cross-overs were observed with polymophic markers at the human homolog, P, of the mouse pink eyed dilute gene, p. Contrary to what has been shown for Caucasoid ty-pos OCA, this condition shows locus homogeneity among SA blacks. The P gene is an excellent candidate for ty-pos OCA and mutations in this gene will confirm its role in causing the common form of Albinism in SA. Numerous P gene mutations have been described in other populations. In an attempt to detect mutations, the P gene cDNA was used to search for structural rearrangements or polymorphisms. Six polymorphisms (plR10/ Scal, 912/ Xbal, 912/ HincII, 912/ TaqI, 1412/ TaqI[two systems] and 1412/ HindIII) were detected with subclones of the P cDNA and haplotypes were determined in each family. None were clearly associated with an Albinism-related rearrangement. However, strong linkage disequilibrium was observed with alleles at loci toward the 5{prime} region of the gene ({triangle}=0.65, 0.57 and 0.80 for the three polymorphisms detected with the 912 subclone), suggesting a major ty-pos OCA mutation in this region. Haplotype analysis provides evidence for a major mutation associated with the same haplotype in individuals with ephelides (8/ 12 OCA chromosomes) and those without ephelides (24:30). The presence of other ty-pos OCA associated haplotypes indicates several other less common mutations.
All About Albinism
The degree of Albinism varies
among animal groups. Some
researchers working with mammals
estimate that true albinos occur in
about one in 10,000 births. Some
of our Conservation Department
hatcheries have seen albino catfish
produced as frequently as one in
20,000 fish. Yet some researchers
working with birds found that Albinism
occurs in 17 of 30,000 individuals,
or one of 1,764 birds.
Oculocutaneous albinism type 2
The Online Mendelian Inheritance in Man (OMIM) database contains genetics resources that discuss Oculocutaneous Albinism type 2. Click on the link to go to OMIM and review these resources.
Visual Function and Ocular Pigmentation in Albinism - Full Text View - ClinicalTrials.gov
Visual function and ocular pigmentation are being studied in patients with Albinism and other disorders associated with hypopigmentation. The degree of ocular pigmentation is assessed clinically by estimating the melanin content of the iris, retinal pigment epithelium, and choroid. Visual function is measured in the conventional manner to study central vision, and electrophysiological methods to detect a misrouting of the visual pathways. The purpose of this study is to document the visual deficit and the pigmentary changes of patients with Albinism, to observe their natural course, and to determine whether misrouting of the visual pathways is present and is correlated with pigmentation.
Oculocutaneous albinism type 1B
The Online Mendelian Inheritance in Man (OMIM) database contains genetics resources that discuss Oculocutaneous Albinism type 1B. Click on the link to go to OMIM and review these resources.
Albinism and Hypo-Pigmentosa
People with Albinism have little or no pigment in the eyes, skin, and hair (or in some cases in the eyes alone). They have inherited from their parents an altered copy of a genes that do not allow the body to make the usual amounts of a pigment called melanin.
NIH Guide: OCULAR ALBINISM (OA1) AND RETINAL GANGLION CELL DEVELOPMENT
OA1 is the most common form of ocular Albinism. It is an inherited, X-linked disorder wherein the RPE lacks pigment while the skin and hair are normal. The pathology of OA1 includes disturbances in the factors which affect the number of retinal cells and their proliferation during early retinal development. These errors in RGC axon development and guidance lead to developmental abnormalities such as myopia. A less frequently occurring form of ocular Albinism, oculocutaneous Albinism or OCA, is a group of congenital, mostly autosomal recessive but occasionally autosomal dominant disorders. OCA is characterized by a generalized disruption in melanin pigment synthesis in the hair, skin, and eyes. OCA and OA1 give rise to a similar constellation of visual disorders.
DLEG - Meeting of Flint Area Albinism Network (FAAN), July 7, 2005
This "Living With Albinism Support Group" is for individuals and families with Albinism living in Genesee, Huron, Lapeer, St. Clair, Sanilac, and Tuscola counties and surrounding areas. The purpose of FAAN is to teach self-advocacy and to educate and empower individuals and their families by providing helpful resources and tools needed to overcome obstacles in education, employment, independent living, transportation, and other aspects of life.
NIH Guide: OCULAR ALBINISM AND THE NEUROSCIENCE OF RETINAL GANGLION CELL AXON GUIDANCE
Albinism includes a group of genetic disorders that share a reduction in retinal melanin pigmentation and significant visual abnormalities. OA1 is the most common form of ocular Albinism; patients suffer from nystagmus, strabismus, foveal hypoplasia, photophobia, refractive errors, and decreased visual acuity, which can compromise vocational choice and quality of life. The less frequently occurring oculocutaneous Albinism (OCA) is a heterogeneous group of congenital, mostly autosomal recessive but occasionally autosomal dominant disorders. These include the Angelman, Chediak-Higashi, Hermansky- Pudlak, Prader-Willi, and Waardenburg syndromes. OCA is characterized by a generalized disruption in melanin pigment synthesis in the hair, skin, irides, and eyeground. OCA and OA1 have similar visual outcomes.
Oculocutaneous Albinism Type 1 -- GeneReviews -- NCBI Bookshelf
Congenital motor nystagmus. Congenital motor nystagmus is an autosomal dominant or X-linked dominant disorder in which ocular structure is normal but nystagmus results in reduced visual acuity. Individuals with congenital motor nystagmus often have compensatory head movement (a "head bob") or posture (a "head turn") to reduce the amount of nystagmus and hence to improve acuity. Head bobbing and head turning are less commonly observed in individuals with Albinism. Visual evoked potential (VEP) analysis is normal in congenital motor nystagmus. Some individuals with congenital motor nystagmus have been reported to have retinal hypopigmentation and foveal abnormalities, but the studies were done before molecular analysis of the different types of OCA was available, suggesting that these reports may have included individuals with OCA who were incorrectly diagnosed as having congenital motor nystagmus.
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