[利用(GT)n多态性DNA标记检测唐氏综合征中额外21号染色体的减数分裂起源的研究]

[Studies of meiotic origin of the extra chromosome 21 in Down syndromes detected by using (GT)n polymorphic DNA markers].

作者信息

Shi Q H, Zhang J X, Pan S J, Zhang X R, Chen Y F, Shan X N, Huang H J, Yu L, Zhao S Y, Zheng Q P, Adler I D

机构信息

Department of Biology, Nanjing Normal University.

出版信息

Yi Chuan Xue Bao. 1998 Dec;25(6):478-84.

PMID:10465893

Abstract

The polymorphics of two pericentric (GT)n sequences on the long arm of human chromosome 21 have been analyzed after PCR amplification, PAGE and Ag-staining for the first time in 50 Chinese Han people, and were used to detect meiotic origin of the extra chromosome 21 in Down syndromes. Six and 5 alleles were found in Chinese Han people for D21S215 and D21S120, respectively, with observed heterozygosities of 0.68 and polymorphic information content PIC, 0.67 and 0.65. For 17 Down syndromes whose parental origin of the extra chromosome 21 were known, meiotic origin of the extra chromosome 21 were determined in 16 cases, with 7 and 4 maternal meiosis I and II nondisjunction, 2 and 3 paternal meiosis I and II, respectively. The possible biological significance of the study on origin of the extra chromosome 21 has been discussed.

摘要

首次对50名中国汉族人进行PCR扩增、聚丙烯酰胺凝胶电泳（PAGE）和银染后，分析了人类21号染色体长臂上两个近着丝粒（GT）n序列的多态性，并用于检测唐氏综合征中额外21号染色体的减数分裂起源。在中国汉族人群中，D21S215和D21S120分别发现了6个和5个等位基因，观察杂合度分别为0.68，多态信息含量（PIC）分别为0.67和0.65。对于17例已知额外21号染色体亲代来源的唐氏综合征患者，16例确定了额外21号染色体的减数分裂起源，其中7例和4例分别为母源减数分裂I和II不分离，2例和3例分别为父源减数分裂I和II。讨论了额外21号染色体起源研究的可能生物学意义。