Molecular Spectrum of α- and β-Thalassemia Mutations in a Large Ethnic Hakka Population in Southern China.

Thalassemia is one of the most prevalent inherited disorders in southern China. However, there have been few reports on molecular characterization of α- and β-thalassemia (α- and β-thal) in the large Hakka population living in Meizhou, a city with high incidence of thalassemia in China. A total of 11,631 in- and outpatients in the Hakka area were analyzed by DNA-based α- and β-thal testing. Of all the samples, 4280 mutant chromosomes were detected, accounting in a total of 35.98%, of which 2864 (24.82%) α-thal mutants were detected, 1268 (10.09%) β-thal mutants were detected, 148 (1.27%) α- and β-thal mutants were detected. The following mutations - -SEA /αα (Southeast Asian deletion), βA /βA ; αα/αα, IVS-II-654 (C>T) (HBB: c.316-197C>T)/βA ; αα/αα, codons 41/42 (-TCTT) (HBB: c.126_129delCTTT)/βA ; and -α3.7 /αα, βA /βA were the most common thalassemia genotypes. The most common thalassemia genotype in the Hakka population in Meizhou was α-thal. In order to reduce the incidence of severe thalassemia in children, a prevention and control strategy should be established based on the distribution data of thalassemia genotyping. Our findings provide a valuable reference for clinical institutions or local governments to reduce the prevalence of thalassemia in the subtropical regions in the world.