Analysis of α-hemoglobin-stabilizing protein (AHSP) gene as a genetic modifier to the phenotype of β-thalassemia in Southern China

α-Hemoglobin-stabilizing protein (AHSP) is a molecular chaperon binding specifically to free α-globin. It is considered to be a potential modifier of β-thalassemia. In order to find out if AHSP affects the phenotype of β-thalassemia carriers in southern China, we analyzed AHSP gene in 365 β-thalassemia subjects which was identified in 5789 consecutive blood samples from southern China. 8 SNPs were detected including two rare SNPs which were reported by us for the first time and two novel missense mutations. One missense mutation, A to T transversion at gene position 12750, substituting aspartic acid for valine at amino acid position 29 (AHSP D29V), was detected in three β-thalassemia carriers respectively. The other AHSP missense mutation, 12831 A > T, which substitutes valine for glycine at amino acid position 56 (AHSP V56G), was identified in only one sample. Neither of the two missense mutations leads to obvious phenotypic change to the β-thalassemia carries. A genetic association study between AHSP gene and the phenotype of β-thalassemia subjects was conducted simultaneously. No significant association has been found between specific AHSP alleles or haplotypes and the disease severity of β-thalassemia. Our study suggested that AHSP is not a significant genetic modifier of β-thalassemia in southern China.