Prenatal diagnosis of β-thalassemia in Guangxi Zhuang Autonomous Region, China

The aim of this study was to establish a comprehensive prenatal diagnosis service and to control the birth of thalassemia children in Guangxi Zhuang Automonous Region, China. Prenatal diagnosis was performed in 1,058 couples with 'at risk' beta-thalassemia from Guangxi Zhuang Automonous Region. Fetal samplings were collected by chorionic villus sampling in the first trimester, by amniocentesis in the second trimester and by cordocentesis in the third trimester. DNA analysis was carried out using polymerase chain reaction, reverse dot blot assay, multiplex ligation-dependent probe amplification method and DNA sequencing. Automated high-performance liquid chromatography system was used to analyze the fetal hemoglobin in pregnancies in case mutations were unidentified. A total of 12 different beta-thalassemia mutations were characterized from 2,116 parents. The most common mutation for beta-thalassemia was CD41-42 (-CTTT) followed by CD17 (A -> T). Prenatal testing revealed 315 normal fetuses, 500 carriers and 253 beta-thalassemia major fetuses. The couples having fetuses with beta-thalassemia major were counselled to terminate the pregnancies. Postnatal follow-up confirmed all pregnancies. Our prenatal diagnosis strategy proved to be highly effective in reducing severe thalassemia in pregnant populations.