Longterm sun exposure greatly increases the risk of skin damage and skin cancers, including an. Individuals affected by oculocutaneous albinism have very light skin and lightcolored irises. Albinism is a congenital disorder characterized by complete or partial absence of pigments in hair, skin and eyes. Prevalence is dependent on subtype but has been reported to have an overall incidence of 1 in 16,00020,000 live births. The abnormality in the formation in melanin can involve the melanocytes in the skin, in the hair follicles, and in the eyes, resulting in oculocutaneous albinism oca. Patients with griscelli syndrome ii also have an increased susceptibility to hemophagocytic syndrome.
Albinism can and does affect all ethnic backgrounds. Oculocutaneous albinism archives of disease in childhood. Oculocutaneous albinism oca is a heterogenous group of autosomal recessive disorders affecting melanin synthesis, characterised by congenital hypopigmentation of the skin, hair, and eyes. Dec 18, 20 types of a i i f albinism 1 oculocutaneous albinism oca 1 oculocutaneous albinism oca. Oculocutaneous albinism type 4 oca4 in humans and similar phenotypes in many animal species are caused by variants in the slc45a2 gene, encoding a putative sugar transporter. Seven types of oca caused by mutations in different genes have been recognized. Griscelli syndrome an overview sciencedirect topics. Patients with any form of albinism may have ocular or visual disorders, ranging from severe to mild problems. Seven subtypes and 6 responsible genes all except for type 5 have been described. Oculocutaneous albinism oca is a group of rare genetic disorders of melanin biosynthesis inherited in an autosomal recessive pattern. Oculocutaneous albinism is a form of albinism involving the eyes, the skin cutaneous, and according to some definitions, the hair. Oculocutaneous albinism orphanet journal of rare diseases. Oculocutaneous albinism genetics home reference nih. Oca2 previously called p is the only gene in which mutations are known to cause oculocutaneous albinism type 2.
Molecular basis of oculocutaneous albinism type 1 in lebanese. Oculocutaneous albinism type 1b oca1b is a type of oca1 see this term characterized by skin and hair hypopigmentation. Oculocutaneous albinism oca is a group of rare inherited disorders characterized by a reduction or complete lack of melanin pigment in the skin, hair and eyes. Oculocutaneous albinism type 1 genetic and rare diseases. Albinism is the congenital absence of any pigmentation or coloration in a person, animal or plant, resulting in white hair, feathers, scales and skin and pink eyes in mammals, birds, reptiles, amphibians and fish and invertebrates as well. Oculocutaneous albinism okulicz 2003 journal of the. For the present study, we investigated a bullmastiff with. However, the incidence of oculocutaneous albinism patients in guangxi remains unclear. In the past, albinism has been divided into oculocutaneous albinism and ocular albinism.
Case report a 32 year old male, who was a known case of oculocutaneous albinism, presented with an ulcerated lesion over the right forearm. Article 4 pediatric patient with oculocutaneous albinism. Oculocutaneous albinism both the skin and eyes are affected and can present with varying degrees of pigment. Oculocutaneous albinism type iii oca3, caused by mutations of tyrp1. Oculocutaneous albinism oca involves the eyes, hair, and skin, whereas in ocular albinism oa visual involvement is accompanied by. It involves the skin, hair, and eyes oculocutaneous albinism or may. Albinism and other genetic disorders of pigmentation. Apr 01, 20 oculocutaneous albinism type 1b oca1b is a type of oca1 see this term characterized by skin and hair hypopigmentation, nystagmus, reduced iris and retinal pigment and misrouting of the optic nerves. Types of albinism oculocutaneous albinismcaused by a mutation in 1 of 4 genes. Oculocutaneous albinism nord national organization for.
Oculocutaneous albinism an overview sciencedirect topics. Suzuki t, tomita t 2008 recent advances in genetic analyses of oculocutaneous albinism types 2 and 4. These conditions are caused by mutations in specific genes that are necessary for the production of melanin pigment in specialized cells called melanocytes. Review article mutational analysis of oculocutaneous albinism. Oculocutaneous albinism is a group of rare genetic disorders with autosomal recessive inheritance, characterized by hypopigmentation of skin, hair, and eyes. Albinism, derived from the latin albus, is a group of inherited disorders in which melanin biosynthesis is reduced or absent. All types of oca and ocular albinism oa have similar ocular findings, including various degrees of congenital nystagmus, hypopigmentation of. Oculocutaneous albinism oca is a group of autosomalrecessive conditions characterized by mutations in melanin biosynthesis with resultant absence or reduction of melanin in the melanocytes.
If both the skin and the eyes are affected, it is referred to as oculocutaneous albinism oc albinism. Optos to observe the pigment of the fundus to make a definitive diagnosis. The chediakhigashi syndrome is an inherited disorder characterized by partial oculocutaneous albinism, increased susceptibility to infections, hemorrhagic tendencies, and the presence of enlarged membranebound granules in many cell types including blood leukocytes. A defect in the melanin synthesis pathway, resulting in reduced formation of melanin, is responsible for oculocutaneous albinism.
Oculocutaneous albinism oca is a human autosomalrecessive hypopigmentation disorder with hypopigmentation in the skin, hair, and eyes. Oculocutaneous albinism orphanet journal of rare diseases full. Longterm 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 definition of oculocutaneous. Overall, an estimated 1 in 20,000 people worldwide are born with oculocutaneous albinism. Pubmed is a searchable database of medical literature and lists journal articles that discuss oculocutaneous albinism type 3. Nonsyndromic oculocutaneous albinism nsoca is clinically characterized by the loss of pigmentation in the skin, hair, and iris. Within oca there are two primary types of albinism.
Oca2 previously called p is the only gene in which mutations are known to cause oculocutaneous albinism. Inagaki k, suzuki t, shimizu h, ishii n, umezawa y, et al. Belliappa pemmanda raju, umashankar nagaraju, leena. Oculocutaneous albinism type 2 genetic and rare diseases.
The diagnosis of oca2 is based on clinical findings. Representative fundus photograph of a patient with oculocutaneous albinism. Accessible word version word, 2mb albinism accessible pdf version pdf, 93kb albinism what are the different types of albinism. Genetic analyses of oculocutaneous albinism types 1 and 2. By sabrina basilehermanskypudlack syndrome oculocantous albinism albinis ocular albinism m affects more than just people. Vision problems are present, but eye, hair, and skin color is generally in the normal range. Subtypes include oca1 oca1a and oca1b, oca2, oca3, oca4, oca5, oca6 and oca7. Oculocutaneous albinism is an autosomal recessive disorder that presents with heterogeneous expressivity. For a discussion of genetic heterogeneity of oca, see oca1a. Oculocutaneous albinism type 2 is a genetic condition that affects the coloring pigmentation of the skin, hair, and eyes. In dog, two independent slc45a2 variants are known that cause oculocutaneous albinism in doberman pinschers and several small dog breeds respectively.
Pdf treat oculocutaneous albinism with gene therapy. Molecular outcomes, clinical consequences, and genetic diagnosis. Albinism is caused by a genetic lack of melanin melanin is synthesized from the amino acidtyrosine tyrosinase breaks down tyrosine people with albinism have been passed down anonfunctional tyrosinase allele, which does notallow them to produce melanin. The prevalence of all forms of albinism varies considerably worldwide and has been estimated at approximately 117,000, suggesting that about 1 in 70 people carry a gene for oca. Oculocutaneous albinism is a group of conditions that affect the coloring of the hair and eyes. Oca1 and oca2 are caused by mutations of the tyr and oca2 genes, respectively, which are responsible for most oculocutaneous albinism. Albinism is characterized by reduced pigmentation in the skin and hair with ocular involvement. A kit designed to guide parents and general education teachers in supporting students with albinism in the classroom. Nov 07, 2011 oculocutaneous albinism type 1 is a condition that affects the coloring of the skin, hair, and eyes. If the patients parents are only carriers of albinism each having one albinism gene and one normal gene, they will have enough genetic information to make normal pigment and will not show any signs of albinism. Some people with this disorder never experience changes in pigmentation, but others. The term oculocutaneous albinism oca refers to a group of congenital disorders that are clinically manifested by an absence of pigment of the skin, hair, and eyes, with associated photophobia and nystagmus.
Oculocutaneous albinism oca is a heterogeneous group of autosomal recessive disorders resulting from mutations of the tyrosinase tyr gene and presents with either complete or partial absence. Review article mutational analysis of oculocutaneous. Oculocutaneous albinism oca is a group of hereditary recessive disorder recognized as a loss of pigmentation. Oculocutaneous albinism is a group of conditions that affect coloring pigmentation of the skin, hair, and eyes. Click on the link to view a sample search on this topic. Oculocutaneous pronounced ockyoulowkewtaineeus albinism oca involves the eyes, hair and skin. Longterm sun exposure greatly increases the risk of skin damage and skin cancers, including an aggressive form of skin cancer called melanoma, in. Signs and symptoms include very fair skin, white hair, an increased risk for skin damage with sun exposure, reduced vision sharpness, light colored irises, nystagmus, and photophobia eyes are sensitive to light. With recent advances in molecular research, it is possible to diagnose many of the various albinism conditions on the basis of genetic causation. Genetics, clinical manifestations, and diagnosis of albinism. The main categories of albinism include the following. Symptoms, causes, and diagnosis medical news today.
Oct 17, 2012 oculocutaneous albinism is a group of conditions that affect the coloring of the hair and eyes. Click below to download the full accessible fact sheets for age related macular degeneration. The past classification of albinism was predicated on phenotypic expression, but now molecular biology has defined the condition more accurately. Albinism refers to a group of inherited disorders of the pigment system in which there is a reduction or an absence of melanin formation. A case report casandra solis, od, akron childrens hospital, akron, ohio case report initial visit a twomonthold female was taken to the emergency department when her parents noted an onset of what they described as intermittent shaky movements of the eyes. People with this type of albinism have white or pink hair, skin, and iris color, as well as vision problems. These mutations cause disturbances to get a standard melanin. Albinism is mostly a recessively inherited disease, which means two albinism genes are inherited one from each parent. Oca can derive from mutations in different genes that produce melanin. All types share reduced to absent pigmentation of skin, hair, and eyes, but the clinical phenotypes vary along a broad spectrum of disease severity. Oca is caused by mutations in several genes that control the synthesis of melanin within the melanocytes. Oculocutaneous albinism oca is an autosomal recessive disorder caused by the complete absence or reduction of biosynthesis of melanin in. Oculocutaneous definition of oculocutaneous by medical. Ocular albinism can occur clinically in several forms.
Omim entry % 615312 albinism, oculocutaneous, type v. Apr 01, 20 type 3 oculocutaneous albinism oca3 is a form of oculocutaneous albinism oca. Harvey dvm, phd, dacvp, in veterinary hematology, 2012. Oculocutaneous albinism types 1 and 2 are the most common, but several other types have been described. Sep 19, 2011 oculocutaneous albinism type 2 is a genetic condition that affects the coloring pigmentation of the skin, hair, and eyes. National organization for albinism and hypopigmentation.
It is not a single genetic disease but a collection of inherited disorders which shows a range of diverse phenotypes, and. Ocular albinism oa shares the ocular features of oca including the increased nerve fibre decussation at the optic chiasm. Brown oca, initially identified in africans and african americans with light brown hair and skin, is part of the spectrum of oca2. Oculocutaneous albinism oca is a group of inherited disorders of melanin biosynthesis. Oculocutaneous albinism oca is a heterogenous group of autosomal recessive disorders affecting. Albinism and disease causing pathogens in tanzania. Oculocutaneous albinism refers to a heterogeneous group of autosomal recessive disorders in which melanin is reduced or absent. These mutations result in symptoms affecting vision, as well as skin, hair, and iris color.
Albinism, oculocutaneous, type vii conditions gtr ncbi. Albinism is an autosomal disorder mainly by ophthalmic features with or without complete symptoms. Varied use and interpretation of the terms mean that written reports of albinistic animals can be difficult to verify. Oculocutaneous albinism oca, involves the lack of pigment in the hair, skin and eyes. Oculocutaneous albinism type 1 is a condition that affects the coloring of the skin, hair, and eyes. Reduced visual acuity, photophobia, iris transillumination, foveal hypoplasia, nystagmus, and an abnormal decussation of nerve fibres at the optic chiasm are common features. Sajjad ali shah 1, anwar saeed 1, muhammad irshad 1. There are many other forms of albinism that are less. Oculocutaneous albinism type 2 oca2 is the most common type of albinism worldwide, due to its high prevalence in subsaharan africa, where prevalence ranges from as low as 1 in 15,000 in nigeria to as high as 1 in in selected zimbabwean populations.
Oca is caused due to defects in genes associated with melanin biosynthetic pathway. A 5yearold girl with abnormalities of the skin and hair that were consistent with albinism had nystagmus and photophobia. Her skin color varied from yellow to milky white and hypopigmentation was appreciated by comparison with other family members. Epidemiology oca3 has an estimated prevalence of 18,500 individuals in africa.
Types of albinism while most people with albinism have very light skin and hair, levels of pigmentation can vary depending on ones type of albinism. Oculocutaneous albinism oca is a group of congenital developmental disorder characterized by complete or partial loss of melanin in skin, hair and eye. Types of a i i f albinism 1 oculocutaneous albinism oca 1 oculocutaneous albinism oca. Carrier rates have been documented to be as high as.
Herein, we present a rare case of two caucasian sisters diagnosed with oculocutaneous albinism type 1 oca1. For a general phenotypic description and a discussion of genetic heterogeneity of oculocutaneous albinism, see oca1. Jul 17, 2003 the diagnosis of oca2 is based on clinical findings. Nov 02, 2007 oculocutaneous albinism oca is a group of inherited disorders of melanin biosynthesis characterized by a generalized reduction in pigmentation of hair, skin and eyes. The pigment melanin is missing from the skin, the hair, and the eyes. Clinicoepidemiologic features of oculocutaneous albinism in.
Correction of refractive errors with spectacles or when ageappropriate contact lenses may improve visual acuity. The oculocutaneous albinism 2 oca2 gene lies within the qtl for albinism, and different deletions in coding regions of this gene are found in pachon and molino cavefish, suggesting convergence. For language access assistance, contact the ncats public information officer. Oculocutaneous albinism type 1 oca1 results from mutations in the tyrosinase gene, which lead to partial or complete loss of activity of the. Oculocutaneous albinism type 3 genetic and rare diseases.
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