Oculocutaneous albinism type 1

General Information (adopted from Orphanet):

Synonyms, Signs: OCA1
Number of Symptoms 14
OrphanetNr: 352731
OMIM Id: 203100
606952
ICD-10: E70.3
UMLs:
MeSH:
MedDRA:
Snomed:

Prevalence, inheritance and age of onset:

Prevalence: <= 2.5 of 100 000 - PMID: 17980020 [IBIS]
Inheritance: Autosomal recessive
Monogenic
- PMID: 3109790 [IBIS]
Age of onset: Neonatal
Infancy
- PMID: 9613388 [IBIS]

Disease classification (adopted from Orphanet):

Parent Diseases: Oculocutaneous albinism
 -Rare eye disease
 -Rare genetic disease
 -Rare skin disease

Comment:

Albinism is an autosomal recessive disorder in which congenital hypopigmentation in the skin, hair and eyes (OCA)) or primarily in the eye (ocular albinism or OA) is associated with severe photosensitivity to ultraviolet radiation, and characteristic abnormalities in the visual system including nystagmus, foveal hypoplasia, misrouting of the optic fibers at the chiasm and greatly decreased visual acuity.The TYR gene which encodes a copper-containing enzyme that catalyzes the first two steps in the melanin biosynthetic pathway is responsible for OCA type I (OCAI). To date, 109 pathogenic mutations have been reported in the TYR gene (PMID:11295837).

Symptom Information: Sort by abundance 

1
(HPO:0007750) Hypoplasia of the fovea 11860983 IBIS 11 / 7739
2
(HPO:0001107) Ocular albinism 3109790 IBIS 40 / 7739
3
(HPO:0000486) Strabismus 1951438 IBIS 576 / 7739
4
(HPO:0000613) Photophobia 19060277 IBIS 158 / 7739
5
(HPO:0000483) Astigmatism 9613388 IBIS 67 / 7739
6
(HPO:0000639) Nystagmus 115122 IBIS 555 / 7739
7
(HPO:0007663) Reduced visual acuity 115122 IBIS 100 / 7739
8
(HPO:0000505) Visual impairment 8190479 IBIS 297 / 7739
9
(HPO:0000545) Myopia 1951438 IBIS 286 / 7739
10
(HPO:0000635) Blue irides 8190479 IBIS 25 / 7739
11
(HPO:0011364) White hair 13680365 IBIS 4 / 7739
12
(HPO:0001022) Albinism 19060277 IBIS 43 / 7739
13
(HPO:0200098) Absent skin pigmentation 15059699 IBIS 2 / 7739
14
(HPO:0003577) Congenital onset 15059699 IBIS 133 / 7739

Associated genes:

TYR;

ClinVar (via SNiPA)

Gene symbol Variation Clinical significance Reference

Additional Information:

Diagnosis GeneReviews The diagnosis of oculocutaneous albinism type 1 (OCA1) [Creel et al 1990] is established by the presence of the following:...
Clinical Description GeneReviews Individuals with all variations of OCA1 have white or nearly white scalp hair, brows, and lashes; white skin; and blue irides with extensive transillumination at birth. The presence of white scalp hair at birth should not be the exclusive clinical criterion for OCA1 because some persons with OCA2 may seem exceedingly fair in the first six to twelve months of life as well. ...
Genotype-Phenotype Correlations GeneReviews OCA1A is caused by null mutations of TYR that produce a completely inactive or an incomplete tyrosinase enzyme polypeptide [Gronskov et al 2007, Simeonov et al 2013]. The total lack of tyrosinase enzyme function blocks the first step of the melanin biosynthetic pathway and, thus, no melanin forms in any melanocyte. ...
Differential Diagnosis GeneReviews Table 2: Oculocutaneous Albinism: OMIM Phenotypic Series...
Management GeneReviews To establish the extent of disease and needs of an individual diagnosed oculocutaneous albinism type 1 (OCA1), the following evaluations are recommended: ...
Molecular genetics GeneReviews Information in the Molecular Genetics and OMIM tables may differ from that elsewhere in the GeneReview: tables may contain more recent information. —ED....