Platelet glycoprotein (GP) V polymorphisms in Japanese.

The glycoprotein (GP) V is a subunit of a platelet receptor for von Willebrand factor, the GPIb/IX/V complex. Recently, polymorphisms in the GPV gene, four involving amino acid changes and five silent, were identified. We developed an allele-specific restriction method to determine the gene frequencies of the non-synonymous substitutions in Japanese and Caucasians. The gene frequencies for 341Gly/Arg polymorphism were 0.94 for 341Gly and 0.06 for 341Arg, and 0.95 for 341Gly and 0.05 for 341Arg, in Japanese and Caucasians, respectively. We could not find rare variants for 114Asp/Tyr, 273Met/Ile or 397Leu/Arg. Flow cytometric analysis showed that the 341Arg variant is expressed normally on the platelet membranes, suggesting the possibility of the involvement of the 341Gly/Arg polymorphism as a platelet alloantigen.