Albinism, Oculocutaneous: Heterogeneous group of autosomal recessive disorders comprising at least four recognized types, all having in common varying degrees of hypopigmentation of the skin, hair, and eyes. The two most common are the tyrosinase-positive and tyrosinase-negative types.Albinism: General term for a number of inherited defects of amino acid metabolism in which there is a deficiency or absence of pigment in the eyes, skin, or hair.Monophenol Monooxygenase: An enzyme of the oxidoreductase class that catalyzes the reaction between L-tyrosine, L-dopa, and oxygen to yield L-dopa, dopaquinone, and water. It is a copper protein that acts also on catechols, catalyzing some of the same reactions as CATECHOL OXIDASE. EC 1.14.18.1.Hermanski-Pudlak Syndrome: Syndrome characterized by the triad of oculocutaneous albinism (ALBINISM, OCULOCUTANEOUS); PLATELET STORAGE POOL DEFICIENCY; and lysosomal accumulation of ceroid lipofuscin.Hypopigmentation: A condition caused by a deficiency or a loss of melanin pigmentation in the epidermis, also known as hypomelanosis. Hypopigmentation can be localized or generalized, and may result from genetic defects, trauma, inflammation, or infections.Eye Color: Color of the iris.Albinism, Ocular: Albinism affecting the eye in which pigment of the hair and skin is normal or only slightly diluted. The classic type is X-linked (Nettleship-Falls), but an autosomal recessive form also exists. Ocular abnormalities may include reduced pigmentation of the iris, nystagmus, photophobia, strabismus, and decreased visual acuity.Melanosomes: Melanin-containing organelles found in melanocytes and melanophores.Nystagmus, Pathologic: Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al., Principles of Neurology, 6th ed, p272)Skin Pigmentation: Coloration of the skin.Melanocytes: Mammalian pigment cells that produce MELANINS, pigments found mainly in the EPIDERMIS, but also in the eyes and the hair, by a process called melanogenesis. Coloration can be altered by the number of melanocytes or the amount of pigment produced and stored in the organelles called MELANOSOMES. The large non-mammalian melanin-containing cells are called MELANOPHORES.Membrane Transport Proteins: Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.Pigmentation: Coloration or discoloration of a part by a pigment.Chediak-Higashi Syndrome: A form of phagocyte bactericidal dysfunction characterized by unusual oculocutaneous albinism, high incidence of lymphoreticular neoplasms, and recurrent pyogenic infections. In many cell types, abnormal lysosomes are present leading to defective pigment distribution and abnormal neutrophil functions. The disease is transmitted by autosomal recessive inheritance and a similar disorder occurs in the beige mouse, the Aleutian mink, and albino Hereford cattle.Electronystagmography: Recording of nystagmus based on changes in the electrical field surrounding the eye produced by the difference in potential between the cornea and the retina.Catechol Oxidase: An enzyme of the oxidoreductase class that catalyzes the reaction between catechol and oxygen to yield benzoquinone and water. It is a complex of copper-containing proteins that acts also on a variety of substituted catechols. EC 1.10.3.1.Melanins: Insoluble polymers of TYROSINE derivatives found in and causing darkness in skin (SKIN PIGMENTATION), hair, and feathers providing protection against SUNBURN induced by SUNLIGHT. CAROTENES contribute yellow and red coloration.Hair Color: Color of hair or fur.Puerto Rico: An island in the Greater Antilles in the West Indies. Its capital is San Juan. It is a self-governing commonwealth in union with the United States. It was discovered by Columbus in 1493 but no colonization was attempted until 1508. It belonged to Spain until ceded to the United States in 1898. It became a commonwealth with autonomy in internal affairs in 1952. Columbus named the island San Juan for St. John's Day, the Monday he arrived, and the bay Puerto Rico, rich harbor. The island became Puerto Rico officially in 1932. (From Webster's New Geographical Dictionary, 1988, p987 & Room, Brewer's Dictionary of Names, 1992, p436)Platelet Storage Pool Deficiency: Disorder characterized by a decrease or lack of platelet dense bodies in which the releasable pool of adenine nucleotides and 5HT are normally stored.Adaptor Protein Complex beta Subunits: A family of large adaptin protein complex subunits of approximately 90-130 kDa in size.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Pedigree: The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.Folklore: The common orally transmitted traditions, myths, festivals, songs, superstitions, and stories of all peoples.Iris Diseases: Diseases, dysfunctions, or disorders of or located in the iris.Oxidoreductases: The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)Frameshift Mutation: A type of mutation in which a number of NUCLEOTIDES deleted from or inserted into a protein coding sequence is not divisible by three, thereby causing an alteration in the READING FRAMES of the entire coding sequence downstream of the mutation. These mutations may be induced by certain types of MUTAGENS or may occur spontaneously.Nystagmus, Congenital: Nystagmus present at birth or caused by lesions sustained in utero or at the time of birth. It is usually pendular, and is associated with ALBINISM and conditions characterized by early loss of central vision. Inheritance patterns may be X-linked, autosomal dominant, or recessive. (Adams et al., Principles of Neurology, 6th ed, p275)DNA Mutational Analysis: Biochemical identification of mutational changes in a nucleotide sequence.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Polymorphism, Single-Stranded Conformational: Variation in a population's DNA sequence that is detected by determining alterations in the conformation of denatured DNA fragments. Denatured DNA fragments are allowed to renature under conditions that prevent the formation of double-stranded DNA and allow secondary structure to form in single stranded fragments. These fragments are then run through polyacrylamide gels to detect variations in the secondary structure that is manifested as an alteration in migration through the gels.Homozygote: An individual in which both alleles at a given locus are identical.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Exons: The parts of a transcript of a split GENE remaining after the INTRONS are removed. They are spliced together to become a MESSENGER RNA or other functional RNA.Chromatophores: The large pigment cells of fish, amphibia, reptiles and many invertebrates which actively disperse and aggregate their pigment granules. These cells include MELANOPHORES, erythrophores, xanthophores, leucophores and iridiophores. (In algae, chromatophores refer to CHLOROPLASTS. In phototrophic bacteria chromatophores refer to membranous organelles (BACTERIAL CHROMATOPHORES).)Bacterial Chromatophores: Organelles of phototrophic bacteria which contain photosynthetic pigments and which are formed from an invagination of the cytoplasmic membrane.Animal Communication: Communication between animals involving the giving off by one individual of some chemical or physical signal, that, on being received by another, influences its behavior.Agouti Signaling Protein: A secreted protein of approximately 131 amino acids (depending on species) that regulates the synthesis of eumelanin (brown/black) pigments in MELANOCYTES. Agouti protein antagonizes the signaling of MELANOCORTIN RECEPTORS and has wide distribution including ADIPOSE TISSUE; GONADS; and HEART. Its overexpression in agouti mice results in uniform yellow coat color, OBESITY, and metabolic defects similar to type II diabetes in humans.Dictionaries, MedicalVisual Acuity: Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.Refractive Errors: Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Ophthalmology: A surgical specialty concerned with the structure and function of the eye and the medical and surgical treatment of its defects and diseases.Myopia: A refractive error in which rays of light entering the EYE parallel to the optic axis are brought to a focus in front of the RETINA when accommodation (ACCOMMODATION, OCULAR) is relaxed. This results from an overly curved CORNEA or from the eyeball being too long from front to back. It is also called nearsightedness.PakistanWalker-Warburg Syndrome: Rare autosomal recessive lissencephaly type 2 associated with congenital MUSCULAR DYSTROPHY and eye anomalies (e.g., RETINAL DETACHMENT; CATARACT; MICROPHTHALMOS). It is often associated with additional brain malformations such as HYDROCEPHALY and cerebellar hypoplasia and is the most severe form of the group of related syndromes (alpha-dystroglycanopathies) with common congenital abnormalities in the brain, eye and muscle development.Carbidopa: An inhibitor of DOPA DECARBOXYLASE, preventing conversion of LEVODOPA to dopamine. It is used in PARKINSON DISEASE to reduce peripheral adverse effects of LEVODOPA. It has no antiparkinson actions by itself.Levodopa: The naturally occurring form of DIHYDROXYPHENYLALANINE and the immediate precursor of DOPAMINE. Unlike dopamine itself, it can be taken orally and crosses the blood-brain barrier. It is rapidly taken up by dopaminergic neurons and converted to DOPAMINE. It is used for the treatment of PARKINSONIAN DISORDERS and is usually given with agents that inhibit its conversion to dopamine outside of the central nervous system.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Epistasis, Genetic: A form of gene interaction whereby the expression of one gene interferes with or masks the expression of a different gene or genes. Genes whose expression interferes with or masks the effects of other genes are said to be epistatic to the effected genes. Genes whose expression is affected (blocked or masked) are hypostatic to the interfering genes.

Altered trafficking of lysosomal proteins in Hermansky-Pudlak syndrome due to mutations in the beta 3A subunit of the AP-3 adaptor. (1/138)

Hermansky-Pudlak syndrome (HPS) is a genetic disorder characterized by defective lysosome-related organelles. Here, we report the identification of two HPS patients with mutations in the beta 3A subunit of the heterotetrameric AP-3 complex. The patients' fibroblasts exhibit drastically reduced levels of AP-3 due to enhanced degradation of mutant beta 3A. The AP-3 deficiency results in increased surface expression of the lysosomal membrane proteins CD63, lamp-1, and lamp-2, but not of nonlysosomal proteins. These differential effects are consistent with the preferential interaction of the AP-3 mu 3A subunit with tyrosine-based signals involved in lysosomal targeting. Our results suggest that AP-3 functions in protein sorting to lysosomes and provide an example of a human disease in which altered trafficking of integral membrane proteins is due to mutations in a component of the sorting machinery.  (+info)

Abnormal expression and subcellular distribution of subunit proteins of the AP-3 adaptor complex lead to platelet storage pool deficiency in the pearl mouse. (2/138)

The pearl mouse is a model for Hermansky Pudlak Syndrome (HPS), whose symptoms include hypopigmentation, lysosomal abnormalities, and prolonged bleeding due to platelet storage pool deficiency (SPD). The gene for pearl has recently been identified as the beta3A subunit of the AP-3 adaptor complex. The objective of these experiments was to determine if the expression and subcellular distribution of the AP-3 complex were altered in pearl platelets and other tissues. The beta3A subunit was undetectable in all pearl cells and tissues. Also, expression of other subunit proteins of the AP-3 complex was decreased. The subcellular distribution of the remaining AP-3 subunits in platelets, macrophages, and a melanocyte-derived cell line of pearl mice was changed from the normal punctate, probably endosomal, pattern to a diffuse cytoplasmic pattern. Ultrastructural abnormalities in mutant lysosomes were likewise apparent in mutant kidney and a cultured mutant cell line. Genetically distinct mouse HPS models had normal expression of AP-3 subunits. These and related experiments strongly suggest that the AP-3 complex regulates the biogenesis/function of organelles of platelets and other cells and that abrogation of expression of the AP-3 complex leads to platelet SPD.  (+info)

Albinism: its implications for refractive development. (3/138)

PURPOSE: Albinism involves the mutation of one or more of the genes associated with melanin synthesis and has many ramifications for vision. This study focuses on the refractive implications of albinism in the context of emmetropization. METHODS: Refractive, biometric, and visual acuity data were collected for a group of 25 albino individuals that included the following: 18 oculocutaneous (13 tyrosine positive, 5 tyrosine negative); 7 ocular (2 autosomal recessive, 5 sex-linked recessive). Their age range was 3 to 51 years. All exhibited horizontal pendular nystagmus. RESULTS: There were no statistically significant differences relating to albino subtype for any of the measured parameters. All the subjects had reduced visual acuity (mean: 0.90, logMAR) and overall, there was a bias toward hyperopia in their refractive errors (mean: + 1.07 D). However the refractive errors of the group covered a broad range (SD: 4.67 D) and included both high myopia and high hyperopia. An axial origin to the refractive errors is implied by the high correlation between refractive errors and axial lengths. Refractive astigmatism averaged 2.37 D and was consistently with-the-rule and highly correlated with corneal astigmatism, which was also with-the-rule. Meridional analysis of the refractive data indicated that the vertical meridian for hyperopic subjects was consistently nearer emmetropia compared to their horizontal meridian. Myopic subjects showed the opposite trend. CONCLUSIONS: The overall refractive profile of the subjects is consistent with emmetropization being impaired in albinism. However, the refractive errors of hyperopic subjects also can be explained in terms of "meridional emmetropization." The contrasting refractive profiles of myopic subjects may reflect operational constraints of the emmetropization process.  (+info)

The Hermansky-Pudlak syndrome (HPS) protein is part of a high molecular weight complex involved in biogenesis of early melanosomes. (4/138)

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder in which oculocutaneous albinism, bleeding tendency and a ceroid-lipofuscin lysosomal storage disease result from defects of multiple cytoplasmic organelles: melanosomes, platelet dense granules and lysosomes. The HPS polypeptide, a 700 amino acid protein which is unrelated to any known proteins, is likely to be involved in the biogenesis of these different organelles. Here, we show that HPS is a non-glycosylated, non-membrane protein which is a component of two distinct high molecular weight complexes. In non-melanotic cells the HPS protein is contained almost entirely in an approximately 200 kDa complex that is widely distributed throughout the cytosol. In melanotic cells the HPS protein is partitioned between this cytosolic complex and a >500 kDa complex that appears to consist of the approximately 200 kDa complex in association with membranous components. Subcellular fractionation, immunofluorescence and immunoelectron microscopy studies indicate that the membrane-associated HPS complex of melanotic cells is associated with tubulovesicular structures, small non-coated vesicles, and nascent and early-stage melanosomes. These findings suggest that the HPS complex is involved in the biogenesis of early melanosomes.  (+info)

Endoplasmic reticulum retention is a common defect associated with tyrosinase-negative albinism. (5/138)

Tyrosinase is a melanocyte-specific enzyme critical for the synthesis of melanin, a process normally restricted to a post-Golgi compartment termed the melanosome. Loss-of-function mutations in tyrosinase are the cause of oculocutaneous albinism, demonstrating the importance of the enzyme in pigmentation. In the present study, we explored the possibility that trafficking of albino tyrosinase from the endoplasmic reticulum (ER) to the Golgi apparatus and beyond is disrupted. Toward this end, we analyzed the common albino mouse mutation Tyr(C85S), the frequent human albino substitution TYR(T373K), and the temperature-sensitive tyrosinase TYR(R402Q)/Tyr(H402A) found in humans and mice, respectively. Intracellular localization was monitored in albino melanocytes carrying the native mutation, as well as in melanocytes ectopically expressing green fluorescent protein-tagged tyrosinase. Enzymatic characterization of complex glycans and immunofluorescence colocalization with organelle-specific resident proteins established that all four mutations produced defective proteins that were retained in the ER. TYR(R402Q)/Tyr(H402A) Golgi processing and transport to melanosomes were promoted at the permissive temperature of 32 degrees C, but not at the nonpermissive 37 degrees C temperature. Furthermore, evidence of protein misfolding was demonstrated by the prolonged association of tyrosinase mutants with calnexin and calreticulin, known ER chaperones that play a key role in the quality-control processes of the secretory pathway. From these results we concluded that albinism, at least in part, is an ER retention disease.  (+info)

A mutation in Rab27a causes the vesicle transport defects observed in ashen mice. (6/138)

The dilute (d), leaden (ln), and ashen (ash) mutations provide a unique model system for studying vesicle transport in mammals. All three mutations produce a lightened coat color because of defects in pigment granule transport. In addition, all three mutations are suppressed by the semidominant dilute-suppressor (dsu), providing genetic evidence that these mutations function in the same or overlapping transport pathways. Previous studies showed that d encodes a major vesicle transport motor, myosin-VA, which is mutated in Griscelli syndrome patients. Here, using positional cloning and bacterial artificial chromosome rescue, we show that ash encodes Rab27a. Rab GTPases represent the largest branch of the p21 Ras superfamily and are recognized as key players in vesicular transport and organelle dynamics in eukaryotic cells. We also show that ash mice have platelet defects resulting in increased bleeding times and a reduction in the number of platelet dense granules. These defects have not been reported for d and ln mice. Collectively, our studies identify Rab27a as a critical gene for organelle-specific protein trafficking in melanocytes and platelets and suggest that Rab27a functions in both MyoVa dependent and independent pathways.  (+info)

Lysosome-related organelles. (7/138)

Lysosomes are membrane-bound cytoplasmic organelles involved in intracellular protein degradation. They contain an assortment of soluble acid-dependent hydrolases and a set of highly glycosylated integral membrane proteins. Most of the properties of lysosomes are shared with a group of cell type-specific compartments referred to as 'lysosome-related organelles', which include melanosomes, lytic granules, MHC class II compartments, platelet-dense granules, basophil granules, azurophil granules, and Drosophila pigment granules. In addition to lysosomal proteins, these organelles contain cell type-specific components that are responsible for their specialized functions. Abnormalities in both lysosomes and lysosome-related organelles have been observed in human genetic diseases such as the Chediak-Higashi and Hermansky-Pudlak syndromes, further demonstrating the close relationship between these organelles. Identification of genes mutated in these human diseases, as well as in mouse and Drosophila: pigmentation mutants, is beginning to shed light on the molecular machinery involved in the biogenesis of lysosomes and lysosome-related organelles.  (+info)

Leucodystrophy and oculocutaneous albinism in a child with an 11q14 deletion. (8/138)

We report a patient with an undetermined leucodystrophy associated with type 1A oculocutaneous albinism (OCA). Type 1 OCA results from recessive mutations in the tyrosinase gene (TYR) located in 11q14.3. The patient was found by FISH to carry a deletion of at least the first exon of the TYR gene on one chromosome and a (TG) deletion at codon 244/245 on the second chromosome. The existence of the microdeletion suggested that a gene responsible for leucodystrophy was located in the vicinity of the TYR gene. A combination of a test of hemizygosity and contig mapping studies allowed us to map the gene within a 0.6 cM region flanked by microsatellite markers D11S1780 and D11S931.  (+info)

Looking for online definition of oculocutaneous albinism type 4 in the Medical Dictionary? oculocutaneous albinism type 4 explanation free. What is oculocutaneous albinism type 4? Meaning of oculocutaneous albinism type 4 medical term. What does oculocutaneous albinism type 4 mean?
Looking for online definition of Oculocutaneous albinism type 2 in the Medical Dictionary? Oculocutaneous albinism type 2 explanation free. What is Oculocutaneous albinism type 2? Meaning of Oculocutaneous albinism type 2 medical term. What does Oculocutaneous albinism type 2 mean?
Purpose: Oculocutaneous albinism (OCA) is an autosomal recessive disorder. The most common type OCA1 and OCA2 are caused by homozygous or compound heterozygous mutations in the tyrosinase gene (TYR) and OCA2 gene, respectively.This study was to evaluate the molecular basis of oculocutaneous albinism in four Chinese families.. Methods: We examined four non-consanguineous OCA families. The TYR and OCA2 genes of all individuals were amplified by polymerase chain reaction (PCR), sequenced and compared with a reference database.. Results: Four patients, diagnosed as oculocutaneous albinism, presented with milky skin, white or light brown hair and nystagmus. Genetic analyses demonstrated that patient 1 was compound heterozygote for c.1037-7T.A, c.1037-10_11delTT and c.1114delG of TYR gene; patient 2 was heterozygote for c.593C,T and c.1426A,G of OCA2 gene, patient 3 and 4 was compound heterozygote of TYR gene (c.549_510delGT and c.896G,A, c.832C,T and c.985T,C). The heterozygous c.549_510delGT and ...
Purpose: Oculocutaneous albinism Type 1 (OCA1) is an autosomal recessive disorder caused by mutations in the tyrosinase gene. Two subtypes of OCA1 have been described: severe OCA1A with complete absence of tyrosinase activity and less severe OCA1B with residual tyrosinase activity. Here we characterized the recombinant mutant variants of human tyrosinase intra-melanosomal domain mimicking OCA1 genetic changes.. Methods: Recombinant human tyrosinase (residues 19 - 469 of the native protein) and mutant variants, P406L, R402Q, R422Q, R422W, and T373K were prepared using the site-directed mutagenesis, produced in larvae and purified by IMAC and size-exclusion chromatographies. Specific L-DOPA enzyme activities were obtained by the dopachrome absorption at 475 nm. Trp fluorescence ratio (F360 nm/F320 nm) was measured as a function of urea concentration (1-8 M) for the wild type protein and mutant variants using SpectraMax i3 multimode detection platform. Denaturation curves show a sigmoidal, ...
Oculocutaneous albinism (OCA) is a genetic disease characterized by the reduction or deficiency of melanin in eyes, skin, and hair. OCA exhibits genetic heterogeneity. Presently, there are four types
Oculocutaneous albinism (OCA) is a genetically heterogeneous disorder. There are four known types of OCA: OCA1-OCA4. The clinical manifestations of all types of…
Oculocutaneous albinism is a group of conditions that affect coloring (pigmentation) of the skin, hair, and eyes. Affected individuals typically have very fair skin and white or light-colored hair. Long-term sun exposure greatly increases the risk of skin damage and skin cancers, including an aggressive form of skin cancer called melanoma, in people with this condition. Oculocutaneous albinism also reduces pigmentation of the colored part of the eye (the iris) and the light-sensitive tissue at the back of the eye (the retina). People with this condition usually have vision problems such as reduced sharpness; rapid, involuntary eye movements (nystagmus); and increased sensitivity to light (photophobia).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 type 1 is characterized by white hair, very pale skin, and light-colored irises. Type 2 is typically ...
Oculocutaneous albinism (OCA) is caused by a group of genetically heterogeneous inherited defects that result in the loss of pigmentation in the eyes, skin and hair. Mutations in the TYR, OCA2, TYRP1 and SLC45A2 genes have been shown to cause isolated OCA. No comprehensive analysis has been conducted to study the spectrum of OCA alleles prevailing in Pakistani albino populations. We enrolled 40 large Pakistani families and screened them for OCA genes and a candidate gene, SLC24A5. Protein function effects were evaluated using in silico prediction algorithms and ex vivo studies in human melanocytes. The effects of splice-site mutations were determined using an exon-trapping assay. Screening of the TYR gene revealed four known (p.Arg299His, p.Pro406Leu, p.Gly419Arg, p.Arg278*) and three novel mutations (p.Pro21Leu, p.Cys35Arg, p.Tyr411His) in ten families. Ex vivo studies revealed the retention of an EGFP-tagged mutant (p.Pro21Leu, p.Cys35Arg or p.Tyr411His) tyrosinase in the endoplasmic reticulum (ER) at
THE colors and patterns on animal body surfaces are often important for visual communication in the wild and are determined primarily by pigment cells (chromatophores) in vertebrates. The chromatophores are distributed in the skin, and their types, sizes, densities, and physiological activities affect these colors and patterns. Although mouse mutants have contributed greatly to our knowledge of skin- and coat-color formation (see Coat Color Genes, http://www.espcr.org/micemut/), mammals possess only one type of chromatophore, the melanocyte. In fish, up to six chromatophore types (melano-, leuco-, erythro-, xantho-, irido-, and cyanophores) have been identified, and there are two distinctive model species to which molecular genetics can be feasibly applied, the zebrafish and the medaka. Chromatophore studies in these species have successfully provided novel clues to the development, regulation, and interaction of these chromatophores (e.g., Parichy et al. 2000; Fukamachi et al. 2004a; Watanabe ...
Contopoulos-Ioannidis, D./ Evangeliou, A./ ter Laak, H./ de Vries, B./ Pfundt, R./ Scheffer, H./ Smeitink, J./ Tzoufi, M./ Makis, A./ Marinos, E./ Hess, R./ Adams, D./ Huizing, M./ Morava, E. ...
This tyrosinase-positive type of albinism is sometimes called rufous (ROCA) or brown (BOCA) oculocutaneous albinism and is frequently found in dark-skinned individual such as Africans, African-Americans, and Hispanics. Like other types it is inherited in an autosomal recessive pattern. Mutations in the tyrosinase-related protein-1, TYRP1 (9p23), are responsible which seems to lead to an arrest in melanin maturation and a decrease in the amount of insoluble melanin in melanocytes.. Other autosomal recessive types of oculocutaneous albinism are: OCA1 (203100, 606952), OCA2 (203200), and OCA4 (606574). ...
These defects may be passed down (inherited) through families.. The most severe form of albinism is called oculocutaneous albinism. People with this type of albinism have white or pink hair, skin, and iris color. They also have vision problems.. Another type of albinism, called ocular albinism type 1 (OA1), affects only the eyes. The persons skin and eye color are usually in the normal range. However, an eye exam will show that there is no coloring in the back of the eye (retina).. Hermansky-Pudlak syndrome (HPS) is a form of albinism caused by a change to a single gene. It can occur with a bleeding disorder, as well as with lung, kidney, and bowel diseases. ...
The biogenesis of melanosomes is a multistage process that requires the function of cell-type-specific and ubiquitously expressed proteins. OCA2, the product of the gene defective in oculocutaneous albinism type 2, is a melanosomal membrane protein with restricted expression pattern and a potential role in the trafficking of other proteins to melanosomes. The ubiquitous protein complexes AP-3, BLOC-1, and BLOC-2, which contain as subunits the products of genes defective in various types of Hermansky-Pudlak syndrome, have been likewise implicated in trafficking to melanosomes. We have tested for genetic interactions between mutant alleles causing deficiency in OCA2 (pink-eyed dilution unstable), AP-3 (pearl), BLOC-1 (pallid), and BLOC-2 (cocoa) in C57BL/6J mice. The pallid allele was epistatic to pink-eyed dilution, and the latter behaved as a semi-dominant phenotypic enhancer of cocoa and, to a lesser extent, of pearl. These observations suggest functional links between OCA2 and these three ...
Patients/methods This is a retrospective study of 132 albino patients, ranging in age from 0.5 to 35 years. They were divided into four subtypes: OCA1A, OCA1B and OCA1C, and OCA2. Refractive errors were evaluated objectively by cycloplegic refraction and subjectively in cooperative patients. Best corrected visual acuity was assessed binocularly. Refractive errors were divided into three groups-hypermetropia, myopia and astigmatism-to avoid the use of spherical equivalent. ...
The most frequent genetic basis for albinism in Africa is via homozygosity (often via culturally imbedded inbreeding) for an autosomal recessive variant of the gene OCA2 (oculocutaneous albinism type II), which encodes the P protein critically involved in pigmentation [8,102] (figure 1) and whose natural variants in Europeans are linked to skin cancer risk in GWAS [39,103]. Most African albinos have the same 2.7 kb deletion OCA2 mutation, indicative of a founder allele arising before the dispersion of ethnic subgroups throughout Africa 2000-3000 years ago [104]. The same mutation is commonly found in albinos in America of African or mixed African descent [105]. OCA2 type II, unlike type I, retains tyrosinase activity and therefore OCA2 albinos do synthesize pheomelanin (see figure 1) and have a variable capacity to develop pigmented patches or ephelides on exposed skin which may, as in normal white skin, provide some protection from UV damage and cancer [106,107]. Early studies showed that ...
Oculocutaneous albinism is a group of conditions that affect coloring (pigmentation) of the skin, hair, and eyes. Affected individuals typically have very fair skin and white or light-colored hair. Long-term sun exposure greatly increases the risk of skin damage and skin cancers, including an aggressive form of skin cancer called melanoma, in people with this condition. Oculocutaneous albinism also reduces pigmentation of the colored part of the eye (the iris) and the light-sensitive tissue at the back of the eye (the retina). People with this condition usually have vision problems such as reduced sharpness; rapid, involuntary eye movements (nystagmus); and increased sensitivity to light (photophobia).. ...
Predicted to have calcium channel activity and calcium, potassium:sodium antiporter activity. Involved in negative regulation of melanin biosynthetic process. Predicted to localize to trans-Golgi network. Is expressed in brain; ear; embryo mesenchyme; and liver. Used to study ocular albinism. Human ortholog(s) of this gene implicated in oculocutaneous albinism type VI. Orthologous to human SLC24A5 (solute carrier family 24 member 5 ...
Membrane-associated transporter protein (MATP) also known as solute carrier family 45 member 2 (SLC45A2) or melanoma antigen AIM1 is a protein that in humans is encoded by the SLC45A2 gene. SLC45A2 is a transporter protein that mediates melanin synthesis. SLC45A2 is also a melanocyte differentiation antigen that is expressed in a high percentage of melanoma cell lines. A similar sequence gene in medaka fish, B, encodes a transporter that mediates melanin synthesis. Mutations in this gene are a cause of oculocutaneous albinism type 4. Alternative splicing results in multiple transcript variants encoding different isoforms. In melanocytic cell types, the SLC45A2 gene is regulated by microphthalmia-associated transcription factor. SLC45A2 has been found to play a role in pigmentation in several species. In humans, it has been identified as a factor in the light skin of Europeans and as an ancestry-informative marker (AIM) for distinguishing Sri Lankan from European ancestry. SLC45A2 is the ...
SLC45A2 is a transporter protein that mediates melanin synthesis. SLC45A2 is also a melanocyte differentiation antigen that is expressed in a high percentage of melanoma cell lines.[8] A similar sequence gene in medaka fish, B, encodes a transporter that mediates melanin synthesis. Mutations in this gene are a cause of oculocutaneous albinism type 4. Alternative splicing results in multiple transcript variants encoding different isoforms.[7] Protein expression is localized to the melanosome, and analysis of the by knockdown of RNA expression leads to altered melanosome pH potentially altering tyrosinase function by affecting copper binding.[9] In melanocytic cell types, the SLC45A2 gene is regulated by microphthalmia-associated transcription factor.[10][11] SLC45A2 has been found to play a role in pigmentation in several species. In humans, it has been identified as a factor in the light skin of Europeans and as an ancestry-informative marker (AIM) for distinguishing Sri Lankan from European ...
Monies et al. (2017) illustrated the genomic landscape of Saudi Arabia based on the findings of 1000 diagnostic panels and exomes. One patient, an 11-year-old male, suffered from hemimegalencephaly, developmental delay and ADHD. He also had abnormal pigmentation all over his body. Whole exome sequencing helped identify a dual molecular diagnosis in this patient. A heterozygous mutation (c.1557T,G, p.Y519X) was found in exon 8 of the patients TYRP1 gene, associated with oculocutaneous albinism type 3, and a heterozygous variant (c.90G,A, p.W30X) was uncovered in exon 1 of the TGIF1 gene, associated with holoprosencephaly 4. Such dual molecular diagnoses were rare and only occurred in 1.5% of the cohort. ...
Monies et al. (2017) reported the genomic landscape of Saudi Arabia based on the findings of 1000 diagnostic panels and exomes. One patient, an 11-year-old male, suffered from hemimegalencephaly, developmental delay and ADHD. He also had abnormal pigmentation all over his body. Whole exome sequencing helped identify a dual molecular diagnosis in this patient. A heterozygous mutation (c.1557T,G, p.Y519X) was found in exon 8 of the patients TYRP1 gene, associated with oculocutaneous albinism type 3, and a heterozygous variant (c.90G,A, p.W30X) was uncovered in exon 1 of the TGIF1 gene, associated with HPE4. Such dual molecular diagnoses were rare and only occurred in 1.5% of the cohort. Further, given the atypical presentation of the patient, this case helped in the phenotypic expansion of the HPE4 disorder. ...
A group of 45 individuals with the clinical findings of oculocutaneous albinism (OCA) will be randomly assigned to one of 3 treatment groups: treatment with 0.76 mg/kg/d with 25% carbidopa, 0.51 mg/kg/d levodopa with 25% carbidopa [divided into 3 doses/d), or placebo. Subjects will be between ages 3 and 60 years. Blood will be drawn to determine the mutation(s) in the genes that causes OCA. Primary outcome will be binocular best-corrected visual acuity measured with the EVA. Enrollment and 20 week examination will be complete eye exam with fundus photos. At weeks 5, 10, and 15, exams will include just vital signs and BCVA. At all visits, a review of potential side effects will be conducted. Between visits, subjects will be contacted to determine if any side effects have occurred. The study will remain double masked until the last study examination on the last subject has been performed. At that time, the data will be statistically analyzed and subjects will be informed re: treatment assignment, ...
The ocular manifestations in type IV oculocutaneous albinism are similar to those of other types. Nystagmus, strabismus, misrouting of neuronal axons, and foveal hypoplasia are prominent features although there is some clinical heterogeneity among patients. Nystagmus may not be present at birth but is almost always evident by 3-4 months of age. The iris may be pale blue or tan and does not generally darken with age. Poor stereopsis is common. Vision is stable after childhood and usually in the range of 20/100-20/400. ...
Hermansky Pudlak Syndrome Type 2 (HPS2) is a rare disorder associated with mutations in the Adaptor Protein 3 (AP-3) complex, which is involved in sorting transmembrane proteins to lysosomes and related organelles. We now report two unrelated subjects with HPS2 who show a characteristic clinical phenotype of oculocutaneous albinism, platelet and T-lymphocyte dysfunction and neutropenia. The subjects were homozygous for different deletions within AP3B1 (g.del180242-180866, c.del153-156), which encodes the AP-3β3A subunit, resulting in frame shifts and introduction of nonsense substitutions (p.E693fsX13, p.E52fsX11). In the subject with p.E693fsX13, this resulted in expression of a truncated variant β3A protein. Cytotoxic T lymphocyte (CTL) clones from both study subjects showed increased cell-surface expression of CD63 and reduced cytotoxicity. Platelets showed impaired aggregation and reduced uptake of 3H-serotonin. These findings are consistent with CTL granule and platelet dense granule ...
Because four-month-old Leopold Reppond suffers from Oculocutaneous Albinism (OCA), a rare condition which affects the pigmentation of the skin,...
This cute little dude suffers from oculocutaneous albinism, a condition that affects the color of his hair, skin and also his vision. But thanks to some special infant glasses from Miraflex, Leo is able to see his mom and dad for the first time. There wasnt a dry eye in the room. ...
Albinism, oculocutaneous, 4 (OCA4) [MIM:606574]: A disorder of pigmentation characterized by reduced biosynthesis of melanin in the skin, hair and eyes. Patients show reduced or lacking pigmentation associated with classic albinism ocular abnormalities, including decreased visual acuity, macular hypoplasia, optic dysplasia, atypical choroidal vessels, and nystagmus. {ECO:0000269,PubMed:11574907, ECO:0000269,PubMed:14722913, ECO:0000269,PubMed:14961451, ECO:0000269,PubMed:15656822, ECO:0000269,PubMed:17768386, ECO:0000269,PubMed:19865097, ECO:0000269,PubMed:23504663}. Note=The disease is caused by mutations affecting the gene represented in this entry ...
Motor Activity Training Program (MATP) is a so called demonstration event. It takes place on March, 23rd, in the Messe Graz (Hall A, Ground Floor). ...
Most growers start their oca tubers in pots indoors as early as possible, and move them outside to their final planting site as soon as the threat of frost has passed. This gives the longest available growing season, and hence more foliage with which to make more tubers. This is quite logical, but oca grows slowly in Spring, and quickly in late Summer, so the question arises - why squander valuable Spring planting space on widely spaced small plants? Why not treat Oca as a late-planted follow-on crop utilising space made available by the harvest of Spring crops? Worth a try I thought, so these plants ...
Ocular albinism is a form of albinism which, in contrast to oculocutaneous albinism, presents primarily in the eyes.[1] There are multiple forms of ocular albinism, which are clinically similar.[2]:865. Both known genes are on the X chromosome. When the term "autosomal recessive ocular albinism" ("AROA") is used, it usually refers to mild variants of oculocutaneous albinism rather than ocular albinism, which is X-linked.[3]. ...
Ocular and oculocutaneous albinism represent a spectrum of disorders with absent or significantly diminished amount of melanin either across different body tissues - skin, hair, eye (Oculocutaneous Albinism 1 and 2), or exclusively in eye tissues only (Ocular Albinism 1) .. The functionality and the clinical findings are diverse (the phenotype), and no direct correlation has been established to the underlying mutations (genotype).. The common ocular phenotype includes iris transillumination, foveal hypoplasia, nystagmus, reduced visual acuity, refractive error, photosensitivity and abnormal development of the visual pathways with characteristic abnormal routing of ganglion cell axons in the chiasma, resulting in abnormal visually evoked potentials. Current treatment options are limited to optical methods and low vision aids.. The mechanism of melanin pigment formation in the RPE cells and its role in the visual pathways and structures development is not completely understood, but a correlation ...
Its estimated that about one in every 18,000-20,000 people in the United States have some form of albinism.. There are several different forms. Oculocutaneous albinism (OCA) happens when theres a mutation in one gene. OCA results in white skin, white hair, and blue eyes.. X-linked ocular albinism occurs only in men, and manifests as light-colored skin and hair thats still considered within the "normal" range.. Hermansky-Pudlak syndrome has symptoms similar to OCA, but its more common in Puerto Rico and its usually accompanied by blood, lung, and bowel disorders.. And Chediak-Higashi syndrome is a rare version that gives hair a silver cast and causes skin to be grayish. White blood cell counts are often affected as well, making people with this type more prone to infections.. As for eye color in humans with albinism, the red, pink, or purple appearance can show up when the light is just right. While the eyes themselves can be blue or brown, the lack of pigmentation can make them seem ...
COAT color has been a fascinating topic of genetic discussion and discovery for over a century. The pigment genes of mice were one of the first genetic systems to be explored through breeding and transgenic studies. To date, at least 127 loci involved in pigmentation have been described (Silvers 1979; Bennett and Lamoreux 2003). The genes that affect pigmentation in the skin and hair influence other body systems, and many of these genes have been studied in different mammals. One of the most extensively studied examples is oculocutaneous albinism type 1, a developmental disorder in humans that affects pigmentation in the skin and hair, as well as eye development. This disease is caused by mutations in the tyrosinase gene (TYR), which is involved in the first step of melanin production (Toyofuko et al. 2001; Ray et al. 2007).. Horses (Equus caballus) are valued by breeders and enthusiasts for their beauty and variety of coat color and patterns. The genetic mechanisms involved in several different ...
NIH Rare Diseases : 53 The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.Orpha Number: 2786DefinitionOsteoporosis-oculocutaneous hypopigmentation syndrome is characterised by osteoporosis and congenital oculocutaneous hypopigmentation. Three cases have been described in the literature. The mode of inheritance appears to be autosomal recessive.Visit the Orphanet disease page for more resources ...
For the latest news, events and information about the albinism community, subscribe to Albinism InSight today. NOAH is a volunteer organization which provides people with albinism, their families and those that work with them the opportunity to get information, ask questions, share their experiences, and connect with the albinism community. Resources are also available for those doing a report on albino people.
Building a Powerful Impact w/Grassroots Albinism Special Interest Groups!. The Albinism Alliance Group or TAAG is an advocacy network organized to "Celebrate the Beauty of Albinism!" To accomplish this we serve as an informational resource to the community. Were creating a series of information pertinent to understanding living with albinism and related characteristics. TAAG envisions a larger mulch-cultural resource by joining forces with other special interest grassroots organizations.. The Albinism Alliance Group was formed in March of 2003. and created from merging "The Atlanta Area Support Group" and online social network "Blonde Black Cuties". Since then, membership has grown tremendously and we currently have 397 members around the world.. We have furthered endeavors with social networking, online activities, and meet and greets. Additional activities and events have blossomed into meaningful memories by giving people from all walks of life, an opportunity to share experiences of living ...
Originally described in 1959 by Drs. Hermansky and Pudlak, HPS is now known to be a rare autosomal recessive disease of lysosome-related organelles.2 There are several subtypes, but all share oculocutaneous albinism and platelet dysfunction.1 Different subtypes have associated conditions and differ in the affected gene.3 HPS type 1 is the most common subtype and is associated with Puerto Rican heritage due to a founder mutation in this population. HPS types 1 and 4 are associated with granulomatous enterocolitis that is phenotypically similar to CD.1,4,5 A case series of 4 patients reported that 3 of 4 patients had perianal disease, all were treated with infliximab, and 2 of 4 patients had complete response to infliximab at 6 weeks.6 Similar to the patient in Case 1, two of their patients underwent colectomy, one of which was due to severe acute rectal hemorrhage. In a case series of 8 HPS patients with colitis seen on colonoscopy, 1 patient showed perianal disease and 2 patients were treated ...
Looking for Albinism, ocular? Find out information about Albinism, ocular. The state of having colorless chromatophores, which results in the absence of pigmentation in animals that are normally pigmented. A hereditary, metabolic... Explanation of Albinism, ocular
Definition of Hermansky-Pudlak syndrome with photos and pictures, translations, sample usage, and additional links for more information.
Shop Hermansky-Pudlak syndrome 4 protein ELISA Kit, Recombinant Protein and Hermansky-Pudlak syndrome 4 protein Antibody at MyBioSource. Custom ELISA Kit, Recombinant Protein and Antibody are available.
DNA sequences associated with the mouse pink-eyed unstable mutation were identified in the absence of closely linked molecular markers and without prior knowledge of the encoded gene product. This was accomplished by genome scanning,: a technique in which high-resolution Southern blots of genomic DNAs were hybridized to a dispersed and moderately repetitive DNA sequence. In this assay, pink-eyed unstable DNA was distinguished from the DNA of wild-type and revertant mice by enhanced hybridization to one of several hundred resolved fragments. The fragment showing enhanced hybridization in pink-eyed unstable DNA was cloned and found to lie within a DNA duplication that is located close to, or within, the pink-eyed dilution locus. The duplication associated with the mouse pink-eyed unstable mutation may mediate the high reversion frequency characteristic of this mutation.
Albinism in children - What are the chances of a person with albinism passing his problem to their children? X-linked or recesiv. The transmission of albinism will depend on the form involved. A male may have an x-linked or autosomal recessive (ar) form. A female is most likely to have the recessive form. A male would not pass it to his sons but could pass the carrier state to his unaffected daughters who might pass it to her sons. The ar albino only passes a carrier state unless the spouse carries the ar gene.
NOAH is a volunteer organization which provides people with albinism, their families and those that work with them the opportunity to get information, ask questions, share their experiences, and connect with the albinism community. Resources are also available for those doing a report on albino people.
Albinism in Animals - Albinism in animals is rare, but nearly every species can produce offspring with albinism. Learn about albanism in animals.
Hermansky-Pudlak Syndrome の最新の知見2. Hermansky-Pudlak Syndrome 関連蛋白質群 : 膜輸送とメラノソーム生合成に関して Hermansky-Pudlak Syndrome : new insights into membrane trafficking and biogenesis of melanosome ...
Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder, with symptoms such as albinism, prolonged bleeding and cell storage problems.
Warfarin is a frequently prescribed drug for both the treatment and prevention of thromboembolic complications. Although many reports have been published over t...
Albinism consists of a group of inherited abnormalities of melanin synthesis and are typically characterized by a congenital reduction or absence of melanin pigment. Albinism results from defective production of melanin from tyrosine through a complex pathway of metabolic reactions.
Albinism Essay, Research Paper Albinism In the past, albinos were usually treated with fear or awe. They were sometimes killed at birth. Albino births were common enough in some groups not to cause any excitement. For example, among the San Blas Indians of Panama, one in approximately 130 births is an albino.
Humans, animals, and even plants can have albinism, a condition that gives people a kind of pale appearance. Find out more about albinism here.
OCA: "oculocutaneous albinism". *PCM: "paracoccidioidomycosis". *Pronounced as a word or as a string of letters, depending on ...
Type IV oculocutaneous albinism, like other types of human albinism, results in hypopigmentation of the skin and eyes, with ... The gene is best known in humans as being the location of a mutation that results in human type IV oculocutaneous albinism ( ... Wei Li (2008-08-30). "Oculocutaneous Albinism 4". Hermansky-Pudlak Syndrome Database. Newton, JM; Cohen-Barak O; Hagiwara N; ... Albinism Association of Australia. "What is Albinism?". Archived from the original on 2009-09-24. Retrieved 2009-11-02. Rieder ...
TYRP1 Albinism, oculocutaneous, type IA; 203100; TYR Albinism, oculocutaneous, type IB; 606952; TYR Albinism, oculocutaneous, ... CACNA1F Albinism, brown oculocutaneous; 203200; OCA2 Albinism, brown; 203290; ... ATP7A Ocular albinism, type I, Nettleship-Falls type; 300500; GPR143 Oculoauricular syndrome; 612109; HMX1 Oculocutaneous ... MITF Waardenburg syndrome/albinism, digenic; 103470; TYR Waardenburg syndrome/ocular albinism, digenic; 103470; MITF Wagner ...
Oculocutaneous albinism caused by mutations in the OCA2 gene is called oculocutaneous albinism type 2. The prevalence of OCA ... "Mutations of the P gene in oculocutaneous albinism, ocular albinism, and Prader-Willi syndrome plus albinism". N. Engl. J. Med ... "Oculocutaneous albinism type 2". Orphanet. Retrieved 2014-11-09. "OCA2 - oculocutaneous albinism II". Genetics Home Reference ... Certain mutations in OCA2 result in type 2 oculocutaneous albinism. OCA2 encodes the human homologue of the mouse p (pink-eyed ...
... in melanocytes from an individual with brown oculocutaneous albinism: a new subtype of albinism classified as "OCA3"". Am. J. ... Mutations in the mouse Tyrp1 gene are associated with brown pelage and in the human TYRP1 gene with oculocutaneous albinism ... Manga P, Kromberg JG, Box NF, Sturm RA, Jenkins T, Ramsay M (1997). "Rufous oculocutaneous albinism in southern African Blacks ... Sarangarajan R, Boissy RE (2001). "Tyrp1 and oculocutaneous albinism type 3". Pigment Cell Res. 14 (6): 437-44. doi:10.1034/j. ...
The syndrome is associated with oculocutaneous albinism. Persons are prone for infections, especially with Staphylococcus ... People with CHS have light skin and silvery hair (albinism) and frequently complain of solar sensitivity and photophobia. Other ... The decrease in phagocytosis results in recurrent pyogenic infections, albinism and peripheral neuropathy. It occurs in humans ... Associated features include abnormalities in melanocytes (albinism), nerve defects, bleeding disorders. There is no specific ...
"Oculocutaneous albinism type 4 is one of the most common types of albinism in Japan". American Journal of Human Genetics. 74 (3 ... Suzuki T, Inagaki K, Fukai K, Obana A, Lee ST, Tomita Y (January 2005). "A Korean case of oculocutaneous albinism type IV ... GeneReviews/NCBI/NIH/UW entry on Oculocutaneous Albinism Type 4 This article incorporates text from the United States National ... Mutations in this gene are a cause of oculocutaneous albinism type 4. Alternative splicing results in multiple transcript ...
Lay summary - ScienceDaily (September 26, 2011). "Nitisinone for Type 1B Oculocutaneous Albinism - Full Text View". ... and has been suggested as a possible treatment for oculocutaneous albinism. Nitisinone was discovered as part of a program to ... "Nitisinone improves eye and skin pigmentation defects in a mouse model of oculocutaneous albinism". Journal of Clinical ...
Oculocutaneous albinism: clinical, historical and anthropological aspects PMID 9759297 Alí, Maurizio. 2010: "En estado de sitio ... The Guna have a high incidence rate of albinism. In Guna mythology, albinos (or sipus) were given a special place. Albinos in ...
She has oculocutaneous albinism which causes her to have poor vision. Gotell was born and raised in Antigonish, Nova Scotia. ...
January 2006). "Genetic testing for oculocutaneous albinism type 1 and 2 and Hermansky-Pudlak syndrome type 1 and 3 mutations ... Davies, Bh; Tuddenham, Eg (April 1976). "Familial pulmonary fibrosis associated with oculocutaneous albinism and platelet ... is an extremely rare autosomal recessive disorder which results in oculocutaneous albinism (decreased pigmentation), bleeding ... There are three main disorders caused by Hermansky-Pudlak syndrome, which result in these symptoms: Albinism and eye problems: ...
People with oculocutaneous albinism typically have a very low level of melanin production. Albinism is often but not always ... In all, already 17 types of oculocutaneous albinism have been recognized. Each gene is related to different protein having a ... Albinism may be caused by a number of other genes as well, like OCA2, SLC45A2, TYRP1, and HPS1 to name some. ... "Increasing the complexity: new genes and new types of albinism". Wiley Online Library / Pigment Cell & Melanoma Research. ...
Gallagher has oculocutaneous albinism, is visually impaired and competes with a sighted guide. At the 2009 New Zealand Winter ...
Winkler PA (2014). "A Partial Gene Deletion of SLC45A2 Causes Oculocutaneous Albinism in Doberman Pinscher Dogs". PLoS ONE. 9 ( ... Although this is consistent with albinism, the proper characterization of the mutation is currently unknown. The animals are ... commonly known as tyrosinase-positive albinoids, lacking melanin in oculocutaneous structures. This condition is caused by a ...
Another form of Albinism, the "yellow oculocutaneous albinism", appears to be more prevalent among the Amish, who are of ... Oculocutaneous Albinism Archived 2008-12-23 at the Wayback Machine. "Ocular Manifestations of Albinism" "Causes of Variability ... "oculocutaneous albinism". Genetics Home Reference. Retrieved 2017-09-25. Meredith, Paul; Sarna, Tadeusz (2006-12-01). "The ... For example, the most common type, called oculocutaneous albinism type 2 (OCA2), is especially frequent among people of black ...
She has only 7-9% vision owing to oculocutaneous albinism, which causes visual impairment. She met the para-cyclist Anthony ...
This transporter is also known to be involved in oculocutaneous albinism type 4 in humans. This information revealed the first ... Snowflake was diagnosed by scientists as having non-syndromic albinism. The genetic variant for Snowflake's albinism was ... Snowflake presented the typical traits and characteristics of albinism typically seen in humans, including white hair, pinkish ...
... and has a visual disability called oculocutaneous albinism. Esdaile is a goalball player, and is classified as a B2 competitor ...
The name of the gene is derived from the disorder it causes, oculocutaneous albinism type II.) Different SNPs within OCA2 are ... NOAH - What is Albinism? Archived 14 May 2012 at the Wayback Machine. Albinism.org. Retrieved on 23 December 2011. ... Ocular Manifestations of Albinism at eMedicine *^ Wallow; Albert (1997). "The color of the human eye: a review of morphologic ... Ocular albinism and eye color. Normally, there is a thick layer of melanin on the back of the iris. Even people with the ...
... underlie a new form of oculocutaneous albinism, OCA4". American Journal of Human Genetics. 69 (5): 981-8. doi:10.1086/324340. ...
GeneReviews/NCBI/NIH/UW entry on Oculocutaneous Albinism Type 1 Tyrosinase at the US National Library of Medicine Medical ... A mutation in the tyrosinase gene resulting in impaired tyrosinase production leads to type I oculocutaneous albinism, a ... and optic neuronal defects shared in all types of oculocutaneous and ocular albinism". The Alabama Journal of Medical Sciences ... Witkop CJ (Oct 1979). "Albinism: hematologic-storage disease, susceptibility to skin cancer, ...
Online Mendelian Inheritance in Man (OMIM) Albinism, oculocutaneous, type IA -203100 Online Mendelian Inheritance in Man (OMIM ... Imes, D. L.; Geary, L. A.; Grahn, R. A.; Lyons, L. A. (April 2006). "Albinism in the domestic cat (Felis catus) is associated ...
Mutations in the human Matp gene result in several distinct forms of Oculocutaneous albinism, Type IV as well as normal ...
Hermansky-Pudlak syndrome is a disorder of organelle biogenesis in which oculocutaneous albinism, bleeding, and pulmonary ...
Certain alleles of this gene, TYR, at the Color locus, cause oculocutaneous albinism type 1 in humans and the familiar red-eyed ... Albinism Dyschromia Erythrism Heterochromia iridum Leucism Melanism Piebaldism Vitiligo Xanthochromism "Albinism". Encyclopædia ... A similar condition, albinism, is a hereditary condition characterised in animals by the absence of pigment in the eyes, skin, ... This condition is more commonly called albinism. Amelanistic mammals have white hair, pink skin, and eyes that have a pink, red ...
Oculocutaneous albinism (Hermansky-Pudlak syndrome). *Waardenburg syndrome. Tyrosine→Norepinephrine. *Dopamine beta hydroxylase ...
Oculocutaneous albinism type 2 explanation free. What is Oculocutaneous albinism type 2? Meaning of Oculocutaneous albinism ... Looking for online definition of Oculocutaneous albinism type 2 in the Medical Dictionary? ... Related to Oculocutaneous albinism type 2: ocular albinism type 2, Oculocutaneous albinism type 3, oculocutaneous albinism type ... Oculocutaneous albinism type II, Yellow albinism. Albinism, major groups. Generalized (oculocutaneous) albinism. All 6 subtypes ...
Oculocutaneous albinism is a group of conditions that affect coloring (pigmentation) of the skin, hair, and eyes. Explore ... Genetic Testing Registry: Oculocutaneous albinism type 4 *Genetic Testing Registry: Tyrosinase-negative oculocutaneous albinism ... medlineplus.gov/genetics/condition/oculocutaneous-albinism/ Oculocutaneous albinism. ... Type 3 includes a form of albinism called rufous oculocutaneous albinism, which usually affects dark-skinned people. Affected ...
Oculocutaneous albinism (OCA) is a form of albinism involving the eyes (oculo-), the skin (-cutaneous), and according to some ... "Oculocutaneous albinism - Genetics Home Reference". http://ghr.nlm.nih.gov/condition/oculocutaneous-albinism http://www.orpha. ... Four types of oculocutaneous albinism have been described, all caused by a disruption of melanin synthesis and all autosomal ... Overall, an estimated 1 in 20,000 people worldwide are born with oculocutaneous albinism. OCA is caused by mutations in several ...
Oculocutaneous Albinism Type I or -Type 1A (OCA1A) is an autosomal recessive skin disease associated with albinism. This type ... of albinism is caused when the gene OCA1 does not function properly. The location of OCA1 may be written as "11q1.4-q2.1", ...
Tyrosinase gene mutations associated with type IB (yellow) oculocutaneous albinism.. [L B Giebel, R K Tripathi, K M Strunk, J ... oculocutaneous albinism (OCA) and thus have demonstrated that type IB OCA is allelic to type IA (tyrosinase negative) OCA. In ...
There are two types of albinism in humans, i.e. the oculocutaneous albinism and the ocular albinism. In oculocutaneous albinism ... 2 Oculocutaneous albinism. (2007). Retrieved from http://ghr.nlm.nih.gov/condition/oculocutaneous-albinism ... Oculocutaneous albinism is associated with mutations in genes involved in melanin production within the melanocytes.2 Examples ... Both the oculocutaneous and cutaneous albinisms are typically associated with vision problems such as nystagmus, photophobia, ...
Albinism . New York, New York, USA: McGraw-Hill; 2001. * King RA, Oetting WS. Oculocutaneous albinism. In: Nordlund JJ, Boissy ... in melanocytes from an individual with brown oculocutaneous albinism: a new subtype of albinism classified as "OCA3". Am J Hum ... Visual disabilities of oculocutaneous albinism and their alleviation. Trans Ophthalmol Soc U K. 1978;98(4):423-445.. View this ... The tyrosinase-positive oculocutaneous albinism locus maps to chromosome 15q11.2-q12. Am J Hum Genet. 1992;51(4):879-884.. View ...
Baxter, L. L., and W. J. Pavan, 2002 The oculocutaneous albinism type IV gene Matp is a new marker of pigment cell precursors ... Rescue From Oculocutaneous Albinism Type 4 Using Medaka slc45a2 cDNA Driven by Its Own Promoter. Shoji Fukamachi, Masato ... Rescue From Oculocutaneous Albinism Type 4 Using Medaka slc45a2 cDNA Driven by Its Own Promoter. Shoji Fukamachi, Masato ... Rescue From Oculocutaneous Albinism Type 4 Using Medaka slc45a2 cDNA Driven by Its Own Promoter. Shoji Fukamachi, Masato ...
We report 3 cases of posterior staphyloma, each with oculocutaneous albinism (OCA) defined by phenotype and genotype. Two cases ... is typically associated with myopic degeneration and has not been recognized as a cause of reduced visual acuity in albinism. ... Posterior staphyloma in oculocutaneous albinism: another possible cause of reduced visual acuity J AAPOS. 2015 Dec;19(6):562-4. ... We report 3 cases of posterior staphyloma, each with oculocutaneous albinism (OCA) defined by phenotype and genotype. Two cases ...
Oculocutaneous Albinism: Heterogeneous group of autosomal recessive disorders comprising at least four recognized types, all ... Albinism, Yellow Mutant; Albinism, Oculocutaneous; Yellow Mutant Albinism; Albinism, Tyrosinase Negative; Albinism, Tyrosinase ... Oculocutaneous Albinism (Albinism, Yellow Mutant). Subscribe to New Research on Oculocutaneous Albinism ... Mutant Albinisms, Yellow; Tyrosinase-Negative Albinism; Tyrosinase-Positive Albinism; Yellow-Mutant Albinism; Albinism, ...
Brown Oculocutaneous Albinism explanation free. What is Brown Oculocutaneous Albinism? Meaning of Brown Oculocutaneous Albinism ... Looking for online definition of Brown Oculocutaneous Albinism in the Medical Dictionary? ... Brown Oculocutaneous Albinism , definition of Brown Oculocutaneous Albinism by Medical dictionary https://medical-dictionary. ... a href=https://medical-dictionary.thefreedictionary.com/Brown+Oculocutaneous+Albinism,Brown Oculocutaneous Albinism,/a,. * ...
Oculocutaneous albinism (OCA) is a genetic disease characterized by the reduction or deficiency of melanin in eyes, skin, and ... in melanocytes from an individual with Brown oculocutaneous albinism: a new type of albinism classified as "OCA3". American ... Oculocutaneous albinism (OCA) is a genetic disease characterized by the reduction or deficiency of melanin in eyes, skin, and ... 2005). Identification of novel TYR and TYRP1 mutations in oculocutaneous albinism. Clinical Genetics, 68, 182-184.PubMed ...
Oculocutaneous albinism type 3 (OCA3): analysis of two novel mutations in TYRP1 gene in two Chinese patients.. [Kai-hui Zhang, ... Oculocutaneous albinism (OCA) is a genetic disease characterized by the reduction or deficiency of melanin in eyes, skin, and ...
Clinico-epidemiologic features of oculocutaneous albinism in Mexico City Carlos Muller Morales; Juan Carlos Zenteno; Ana María ... Clinico-epidemiologic features of oculocutaneous albinism in Mexico City You will receive an email whenever this article is ... Results : A total of 39 patients with diagnosis of oculocutaneous albinism were included; 20 (51.3%) males and 19 (48.7%) ... Carlos Muller Morales, Juan Carlos Zenteno, Ana María Beauregard; Clinico-epidemiologic features of oculocutaneous albinism in ...
Purpose To evaluate the prevalence of refractive errors in different subtypes of oculocutaneous albinism, and to see if there ... Refractive profile in oculocutaneous albinism and its correlation with final visual outcome ... Refractive profile in oculocutaneous albinism and its correlation with final visual outcome ... Astigmatism was the most common visually significant refractive error across all subtypes of albinism. These results may help ...
Background: Oculocutaneous albinism (OCA) is a genetically heterogeneous disorder of abnormal melanin synthesis, resulting in ... Background: Oculocutaneous albinism (OCA) is a genetically heterogeneous disorder of abnormal melanin synthesis, resulting in ... Mutations in TYR and OCA2 associated with oculocutaneous albinism in Pakistani families ... Mutations in TYR and OCA2 associated with oculocutaneous albinism in Pakistani families ...
Tyr mutations are involved in the genetic disease oculocutaneous albinism type 1 (OCA1), which is described by the complete ( ... A Computational Analysis of Human Tyrosinase to Further Understanding of Oculocutaneous Albinism Type 1 ... A Computational Analysis of Human Tyrosinase to Further Understanding of Oculocutaneous Albinism Type 1 ... A Computational Analysis of Human Tyrosinase to Further Understanding of Oculocutaneous Albinism Type 1. Invest. Ophthalmol. ...
An oculocutaneous albinism that has_material_basis_in an autosomal recessive mutation of SLC45A2 on chromosome 5p13.2. https:// ...
Albinism, Oculocutaneous, Type Iv Albinism, Oculocutaneous, Type Ib Albinism, Oculocutaneous, Type Vii Albinism, Oculocutaneous ... Albinism, Oculocutaneous, Type Vi Albinism, Oculocutaneous, Type Ia Albinism, Oculocutaneous, Type Ii Albinism, Oculocutaneous ... Oculocutaneous, Type V, also known as oca5, is related to syndromic oculocutaneous albinism and oculocutaneous albinism, and ... oculocutaneous albinism 30.3. TYRP1 TYR SLC45A2 SLC24A5 OCA5 OCA2 3. albinism, oculocutaneous, type vii 30.1. SLC45A2 SLC24A5 ...
Oculocutaneous albinism (OCA) is caused by a group of genetically heterogeneous inherited defects that result in the loss of ... From: Molecular genetic studies and delineation of the oculocutaneous albinism phenotype in the Pakistani population ...
Albinism, Oculocutaneous, Type Vi Albinism, Oculocutaneous, Type Ia Albinism, Oculocutaneous, Type Ii Albinism, Oculocutaneous ... Albinism, Oculocutaneous, Type Iv Albinism, Oculocutaneous, Type Ib Albinism, Oculocutaneous, Type Vii Albinism, Oculocutaneous ... is related to oculocutaneous albinism and albinism. An important gene associated with Albinism, Oculocutaneous, Type Vi is ... MalaCards integrated aliases for Albinism, Oculocutaneous, Type Vi:. Name: Albinism, Oculocutaneous, Type Vi 57 29 6 73 ...
Book Appointment Online, View Fees, Reviews Doctors for Oculocutaneous Albinism Treatment in Hyderabad , Practo ... Treatment for oculocutaneous albinism in Hyderabad, find doctors near you. ...
Germline variants in oculocutaneous albinism genes and predisposition to familial cutaneous melanoma. Publikation: Bidrag til ... Several heterozygous variants in oculocutaneous albinism (OCA) genes: TYR, OCA2, TYRP1 and SLC45A2, were present in our CM ... Increasing the complexity: new genes and new types of albinism. Publikation: Bidrag til tidsskrift › Tidsskriftartikel › ...
The prevalence of all forms of albinism varies considerably worldwide and has been estimated at approximately 1/17,000, ... Differential diagnosis includes ocular albinism, Hermansky-Pudlak syndrome, Chediak-Higashi syndrome, Griscelli syndrome, and ... Oculocutaneous albinism (OCA) is a group of inherited disorders of melanin biosynthesis characterized by a generalized ... Mutations of the P gene in oculocutaneous albinism, ocular albinism, and Prader-Willi syndrome plus albinism. N Engl J Med. ...
... : Z-Factor in Doberman Pinschers. Description:. In Doberman pinschers, a 4,081 base pair deletion ... Dog is a carrier for the Oculocutaneous Albinism mutation, and can pass on a copy of the defective gene to its offspring 50% of ... The dog carries two copies of the mutant gene and is homozygous for the Oculocutaneous Albinism. The dog is affected, and will ... Dog tested negative for the Oculocutaneous Albinism gene mutation, and will not pass on the defective gene to its offspring.. ...
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