The Q402 allele has been associated with autosomal recessive ocular albinism when it is in trans with a tyrosinase gene mutation associated with oculocutaneous albinism type 1.
This advance allows for the structure - function analyses of different mutant TYR proteins and correlation with their corresponding human phenotypes; it also provides an important tool to discover drugs that may improve tyrosinase activity and treat OCA1.
Three families with oculocutaneous albinism type 1 and 95 unrelated healthy Chinese individuals with normal pigmentation were screened for mutations in the TYR gene by direct sequencing.
Two subtypes of OCA1 have been described: severe OCA1A with complete absence of tyrosinase activity and less severe OCA1B with residual tyrosinase activity.
We found five novel mutations in the tyrosinase gene involved in the pathogenesis of oculocutaneous albinism type IA or type IB (OCA-1A/B) in five unrelated patients.
We hypothesized that increasing plasma tyrosine concentrations using nitisinone, an FDA-approved inhibitor of tyrosine degradation, could stabilize tyrosinase and improve pigmentation in individuals with OCA1.
We report a method to determine the mutations responsible for tyrosinase related albinism (OCA1) using a combination of polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) analysis and direct DNA cycle sequencing using fluorescently labeled oligonucleotides and an automated DNA sequencer based on infrared fluorescence technology.