Genetic polymorphism of coagulation factor XIIIB subunit in Japanese.

Genetic polymorphism of coagulation factor XIIIB subunit in Japanese has been described, using a thin-layer agarose gel isoelectric focusing followed by immunofixation. Phenotypes of factor XIIIB subunit were essentially classified into three common patterns A, B and AB. It is estimated that the phenotypes are determined by two codominant alleles. A new rare variant B' has been detected in Japanese. Gene frequencies calculated from 304 individuals showed FXIII-BA = 0.735, FXIII-BB = 0.252 and FXIII-BB' = 0.013, respectively. The distribution of phenotypes fitted the Hardy-Weinberg equilibrium.