Prenatal diagnosis of thalassemia: experiences at the Shanghai Children's Hospital.

Using DNA dot-blot hybridization, restriction endonuclease gene mapping with oligonucleotide probes, restriction fragment length polymorphism linkage analysis, and hybridization, prenatal diagnosis was performed for 32 pregnancies at risk for alpha-thalassemia and for 10 pregnancies at risk for beta-thalassemia. The DNA samples were prepared from chorion villi or amniotic fluid cells.