Prenatal diagnosis of alpha and beta thalassemias and hemophilia A: experience in Hong Kong.

Methods and strategies are described for the prenatal diagnosis of three common congenital disorders--alpha and beta thalassemias and hemophilia A. It is important to study the frequency of restriction fragment length polymorphisms and types of molecular defects in specific ethnic groups, since they are known to differ significantly. The studies reported here were carried out in southern Chinese who form the majority of the Hong Kong population. The information obtained is also useful for prenatal diagnosis in southern Chinese migrant populations in Canada, USA, Australia, UK and southeast Asia.