[Single nucleotide polymorphisms of β-globin gene in β-thalassaemia patients].

This study was aimed to analyze the β-globin gene sequence and single nucleotide polymorphisms of the β-globin gene in β-thalassaemia patients from Shenzhen area, and to explore linkage relationships between β-globin gene mutations and single nucleotide polymorphisms. Genomic DNA was extracted from peripheral leukocytes in 125 β-thalassaemia patients from Shenzhen population. β-globin gene was amplified by polymerase chain reaction, mutations and single nucleotide polymorphisms in the β-globin gene were determined by DNA sequencing. The results indicated 10 types of mutation and 12 single nucleotide polymorphism loci were found in the β-globin gene of 114 β-thalassaemia patients. Linkage disequilibrium between mutations and single nucleotide polymorphisms was found in 6 loci including 6 haplotypes among these single nucleotide polymorphism loci in the β-globin gene. It is concluded that a number of single nucleotide polymorphisms is found in the β-globin gene, where an average of one single nucleotide polymorphism every 230 bp there is. Linkage disequilibrium occurs between β-thalassaemia mutations and some haplotypes in single nucleotide polymorphism loci. This study may be helpful to gene diagnosis for β-thalassaemia patients.