RESUMEN
OBJECTIVE: Linkage analysis is a very useful method for prenatal diagnosis of Hemophilia B, especially when a mutation was not identified. Seven polymorphic markers were studied in Korean populations to evaluate the efficiency for prenatal and carrier diagnosis. METHODS: Subjects of this study was 100 healthy Korean women (200 X-chromosomes). Polymerase chain reacton-restriction fragment length polymorphism (PCR-RFLP) method was used to detect SalI, MseI, NruI, DdeI, XmnI, TaqI and HhaI polymorphisms. RESULTS: SalI (-) allele showed the frequency of 0.355 and SalI(+) allele 0.645. MseI(-) allele was 0.645 in frequency and MseI(+) allele was 0.355. SalI and MseI polymorphisms were in complete linkage disequilibrium. And no increase was expected in overall heterozygosity with these two polymorphisms. NruI(-) allele frequency was 0.855 and NruI(+) was 0.145. There was no polymorphism of DdeI, XmnI and TaqI marker systems in Korean population. In HhaI polymorphism, allele frequencies were estimated that HhaI(-) is 0.82 and HhaI(+) is 0.18. CONCLUSION: Only SalI, NruI and HhaI polymorphisms are useful for the diagnosis of hemophilia B in Korean population. Expected heterozygosity for above 3 poylmorphic markers was estimated to be 0.723, and 71 of 100 female subjects were heterozygous for at least one marker system. Korean population showed relatively low extent of polymorphisms compared to Caucasians, Blacks and Japanese. For the effective prenatal diagnosis of hemophilia B with linkage analysis, other polymorphic markers should be evaluated.