Amplification of beta-globin gene from single blastomeres.

Prenatal diagnosis of beta-thalassemia can be performed by chorionic villus sampling as early as the ninth gestational week, and early amniocentesis within 12 weeks of gestation. Selective abortion or termination should be suggested if the fetus is affected. With polymerase chain reaction (PCR) and micromanipulation techniques, the preimplantation diagnosis of beta-thalassemia has become possible. A total of 60 single blastomeres were collected and equally divided at random into two groups. Eight DNA primers (A to H) were designed for 15 mutations of beta-thalassemia in Chinese people. Two beta-globin gene fragments (602 bp and 423 bp) were amplified by PCR through two sequential reactions with two sets of primers (A+B and C+D, E+F and G+H), respectively. The amplified products were confirmed by Southern blotting with DNA probes hybridization. The amplification rates were 54% (16/30) and 60% (18/30), respectively. All of the positive and negative controls showed the presence or absence of amplification, respectively. Our study provides a possible approach for the preimplantation diagnosis of beta-thalassemia.