title: Application of DNA polymorphisms for prenatal diagnosis of beta thalassemia in Chinese.
abstract: Forty-seven Chinese suffering from beta thalassemia major and their parents were studied to establish linkage of the beta thal and beta A genes with 11 restriction site polymorphisms. There is marked linkage disequilibrium at the BamH I site 3' to the beta globin gene, such that, in 31% of pregnancies, absence of the site in the fetus can exclude beta thalassemia major. Using four restriction sites (Hinc II psi beta, Ava II beta, Hind III beta, and BamH I beta), prenatal diagnosis is feasible in all families. In 46% of all cases, a definitive diagnosis can be made, and in the remaining cases, a 50% chance of exclusion is possible. Fetal blood globin chain analysis would be required for the failures. Our experience in nine successive beta thalassemia prenatal diagnosis is also reported.
mesh_terms: D002681:China; D004247:DNA / Q000235:genetics*; D005260:Female; D005312:Fetal Blood / Q000032:analysis; D006801:Humans; D008297:Male; D010375:Pedigree; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D013789:Thalassemia / Q000175:diagnosis* / Q000235:genetics
chemical_list: D004247:DNA