Analysis for single nucleotide polymorphisms of beta-globin gene in beta-thalassaemia carriers / 临床检验杂志

Objective To investigate the single nucleotide polymorphisms(SNP) of beta-globin gene in beta-thalassaemia carrier.Methods The target fragment of beta-globin gene in beta-thalassaemia carriers was first amplified using PCR,the single nucleotide polymorphisms were determined by the automatic DNA sequencing.Results Three single nucleotide polymorphisms were found in the amplified fragment of beta-globin gene from beta-thalassaemia carriers.They were respectively the T/C polymorphism at nucleotide 59 in exon 1,the G/C polymorphism at nucleotide -16 in intron 2,and the T/G polymorphism at nucleotide-74 in intron 2.Conclusion There are some differences in the single nucleotide polymorphisms of the beta-globin gene between beta-thalassaemia carriers and normal subjects.The number of single nucleotide polymorphisms among beta-thalassaemia carriers is lesser.The frequency of bases is also different between beta-thalassaemia carriers and normal subjects.

RFLP Haplotypes of beta-Globin Gene Complex of beta-Thalassemic Chromosomes in Koreans

Korea is in the low-prevalence area of beta-thalassemia and the Korean population has relatively homogenous racial characteristics. Recently, we identified some causative mutations of the Korean beta-thalassemia patients. In order to elucidate the genetic background of beta-thalassemia alleles in Koreans, we determined the restriction fragment length polymorphism (RFLP)-haplotype and framework (FW) in nine beta-thalassemia chromosomes of five different causative mutations by PCR-based method and family linkage study. The result that the haplotype and the framework linked to the initiation codon ATG-->AGG mutation were -+-++-+ and FW3A, respectively, in all of three families in this study suggests a common origin of this mutation at least in Koreans. A novel beta-thalassemia mutation, codons 89/90 -TG, showed discrepancy between -++--++- and FW1, which could be explained by gene conversion. A case of codons 8/9 +G frameshift mutation had +----++ and FW1. The linkage of the two beta-thalassemia mutations, codon 17 AAG-->TAG and codons 41/42 -TTCT, with specific haplotypes and frameworks common to the Koreans and the neighboring countries suggests that those mutations are influenced by the genetic flow from the south China.