台湾地区β地中海贫血基因的DNA多态性单倍型分析

DNA polymorphism haplotype analysis of beta-thalassemia genes in Taiwan.

作者信息

Ko T M, Hsu P M, Hsieh F J, Lin K H, Lee S C, Lee T Y

出版信息

Taiwan Yi Xue Hui Za Zhi. 1989 Feb;88(2):103-7.

Abstract

Twenty unrelated families of homozygous beta-thalassemia were collected for restriction polymorphism haplotype study of the beta-thalassemia (beta T) genes. DNA was extracted from WBC of the family members. With Southern blotting and DNA hybridization, restriction fragment length polymorphisms (RFLPs) were studied at 7 sites within the beta-globin gene cluster, including 5' epsilon-HincII, G gamma-HindIII, A gamma-HindIII, psi beta-HincII,3' psi beta-HincII, beta-AvaII,3' beta-BamHI. From RFLPs of the family members, restriction polymorphism haplotypes of the 40 beta T chromosomes and the 40 normal beta-globin gene (beta A)-bearing chromosomes were constructed. In beta T chromosomes. 26 (65%) belonged to haplotype I (+----++), 12 (30%) to haplotype II (+-----+), 1 (2.5%) to haplotype III (-++-+-+) and 1 (2.5%) to haplotype IV (++---++) which has not been reported in Chinese before. In beta A chromosomes, 12 different haplotypes were found. Seven (17.5%) belonged to haplotype I, 13 (32.5%) to haplotype II, and 6 (15%) to haplotype V (+----+-). The implications of RFLP and haplotyping of beta T genes in terms of molecular defects and prenatal diagnosis are discussed.

摘要

收集了20个无关的纯合β地中海贫血家庭，用于β地中海贫血（βT）基因的限制性多态性单倍型研究。从家庭成员的白细胞中提取DNA。通过Southern印迹和DNA杂交，研究了β珠蛋白基因簇内7个位点的限制性片段长度多态性（RFLP），包括5'ε-HincII、Gγ-HindIII、Aγ-HindIII、ψβ-HincII、3'ψβ-HincII、β-AvaII、3'β-BamHI。根据家庭成员的RFLP，构建了40条βT染色体和40条携带正常β珠蛋白基因（βA）染色体的限制性多态性单倍型。在βT染色体中，26条（65%）属于单倍型I（+----++），12条（30%）属于单倍型II（+-----+），1条（2.5%）属于单倍型III（-++-+-+），1条（2.5%）属于单倍型IV（++---++），此单倍型此前在中国未见报道。在βA染色体中，发现了12种不同的单倍型。7条（17.5%）属于单倍型I，13条（32.5%）属于单倍型II，6条（15%）属于单倍型V（+----+-）。讨论了βT基因RFLP和单倍型分析在分子缺陷和产前诊断方面的意义。