[Restriction fragment length polymorphisms in FVIII:C gene and their application in the linkage analysis of hemophilia A].

The Han people in Guangong province were studied to determine the frequencies of BclI, XbaI, and BglI restriction fragment length polymorphisms (RFLPs) in FVIII:C gene. The incidences for positive BclI, XbaI, and BglI sites were 63.5%, 43.5%, and 100%, respectively. Linkage of BclI and XbaI RFLPs were studied and the result showed that 19.5 percent of positive BclI polymorphic site homozygotes were heterozygous for the XbaI RFLP. Hence combining these two RFLPs was informative for 65.9 percent of females. We implemented carrier detection in two hemophilia A families and prenatal diagnosis in another hemophilia A family with these RFLPs.