A new marker at DXS 115 useful for carrier detection in hemophilia A

In this brief communication we report a new intergenic polymorphism at DXS115 as a marker for detection of heterozygotes in families at risk for hemophilia A. Total genomic DNA was isolated from white blood cells, double digested by KpnI and XbaI and hybridized with EcoRI/SstI fragment of the genomic probe p482.6. The incidence of the polymorphic 5.1-kb fragment was estimated as 0.069 in a German population. A technical advantage of using the XbaI/KpnI RFLP is that both the intragenic XbaI-RFLP in intron 22 of factor VIII gene and the new intergenic RFLP can be evaluated at the same time.