Inverse shifting PCR based prenatal diagnosis of hemophilia‐causative inversions involving int22h and int1h hotspots from chorionic villus samples

Almost one half of severe hemophilia A cases are caused by intron 22 (Inv22) and intron 1 (Inv1) factor VIII gene inversions worldwide. To improve the analysis of the presence of Inv22 and Inv1 from chorionic villus-extracted DNA samples, we applied a recently published approach, inverse shifting-PCR (IS-PCR). Prenatal diagnosis accomplished in two cases showed that IS-PCR is a robust and reliable tool to provide rapid information for genetic counseling for hemophilia-affected families.