Prenatal diagnosis of thalassemia: identification of mutations in conjunction with gene amplification in vitro

Prenatal diagnosis of thalassemia and sickle cell anemia using DNA analysis has been performed in Israel since 1982. Until recently the tests involved analysis of polymorphic markers linked to the beta-globulin gene (RFLP). This method is not suitable for many of the families at risk. The recently developed technique of gene amplification in vitro (PCR) facilitates direct identification of the genetic lesions (mutations) using minimal amounts of DNA. The diagnosis is rapid, reliable and unambiguous and can be made early in pregnancy. Our experience in prenatal diagnosis during the past year is reported. Of 14 diagnoses, 13 were made by direct identification of mutations following PCR.