Oculocutaneous albinism type 1B associated with a functionally significant tyrosinase gene polymorphism detected with Whole Exome Sequencing

  title={Oculocutaneous albinism type 1B associated with a functionally significant tyrosinase gene polymorphism detected with Whole Exome Sequencing},
  author={Rodrigo Mendez and Sumaiya Iqbal and Sebasti{\'a}n A Vishnopolska and Cinthia Mart{\'i}nez and Glenda Dibner and Rocio Aliano and Jonathan J. Zaiat and Germ{\'a}n Biagioli and Cecilia S. Fern{\'a}ndez and Adrian Gustavo Turjanski and Arthur J. Campbell and Graciela Mercado and Marcelo Mart{\'i}},
  journal={Ophthalmic Genetics},
  pages={291 - 295}
ABSTRACT Background: Oculocutaneous albinism (OCA) is a Mendelian disorder characterized by hypopigmentation of the skin, hair, and eyes, hypoplastic fovea, and low vision, known to be caused by mutations in the Tyrosinase (TYR) gene. Among the known TYR variants, some reduce but do not completely eliminate tyrosinase activity, allowing residual production of melanin and resulting in a contradictory assignment as either pathogenic or benign, preventing a precise clinical diagnostic. Materials… 


Two Novel Tyrosinase (TYR) Gene Mutations with Pathogenic Impact on Oculocutaneous Albinism Type 1 (OCA1)
The outcome of this study has extended the genotypic spectrum of OCA1 patients, which paves the way for more efficient carrier detection and genetic counseling.
Mild form of oculocutaneous albinism type 1: phenotypic analysis of compound heterozygous patients with the R402Q variant of the TYR gene
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Mutations of the tyrosinase gene in patients with oculocutaneous albinism from various ethnic groups in Israel.
Among Moroccan Jews with type IA (i.e., tyrosinase-negative) OCA, a highly predominant mutant allele containing a missense substitution, Gly47Asp (G47D) occurs on the same haplotype as in patients from the Canary Islands and Puerto Rico, suggesting that the G47D mutation in these ethnically distinct populations may stem from a common origin.
Tyrosinase and ocular diseases: Some novel thoughts on the molecular basis of oculocutaneous albinism type 1
Albinism-Causing Mutations in Recombinant Human Tyrosinase Alter Intrinsic Enzymatic Activity
The intramelanosomal domains of recombinant wild-type and mutant human tyrosinases are soluble monomeric glycoproteins with activities which mirror their in vivo function, and provide an important tool for the structure – function analyses of different mutant TYR proteins and correlation with their corresponding human phenotypes.
Implementation of an optimized strategy for genetic testing of the Chinese patients with oculocutaneous albinism.
Prenatal genotyping of four common oculocutaneous albinism genes in 51 Chinese families.
Tyrosinase gene mutations in type I (tyrosinase-deficient) oculocutaneous albinism define two clusters of missense substitutions.
11 novel mutations of the tyrosinase gene in Caucasian patients with these 2 forms of type I OCA are described, suggesting that these may correspond to functionally important sites within the enzyme.