甲基化遁逸与保守氨基酸的进化  

Biased Missense G→A Over C→T and Nonsense C→T Over G→A in Disease-Causing Mutations and Their Evolutionary Mechanism

作　　者：张佳[1] 陈琳玲[1] 周翠兰[1] 王吉成 廖端芳[1] 高汉林[1] 李凯[1] 

机构地区：[1]南华大学SNP研究所,湖南衡阳421001 [2]希望城国家医学中心

出　　处：《南华大学学报（医学版）》2005年第2期157-159,共3页Journal of Nanhua University(Medical Edition)

基　　金：湖南省自然科学基金资助 (0 3JJY40 41) ;教育部重点项目 (教技司【2 0 0 5】3号;NO :2 0 5 10 6)

摘　　要：甲基化造成的大量C→T转换,为进化提供了源源不断的突变,而同时其所编码的氨基酸则逐渐丧失了遗传上的保守性。与此相反,由G至A的原发性转换可能甚少,相应密码子所对应的氨基酸则相对稳定,从而使可避免甲基化的GDN和DGN三联密码成为保守氨基酸进化的必要条件。That genetic diseases, including single nucleotide substitution and chromosomal aberrant, are individual sacrifices needed for species evolution for quite a while. Based on this concept, genetic diseases can be used as the most precious in vivo experiment occurred naturally at the research point of view. By focusing on the leading mutations, single nucleotide substitution caused missense change, we recognized that for missense there is a biased G→A over C→T both at certain individual genes and at genome level. Furthermore, there is a C→T over G→A bias in nonsense mutations. The underlying mechanism of these observed mutation biases in evolution are discussed.

关 键 词：甲基化遁逸 进化 保守氨基酸 G:T→A:C转换 错义突变 

分 类 号：Q786[生物学—分子生物学]