功能基因中的微卫星序列

微卫星序列广泛存在真核生物和一些原核生物的基因组中,它在基因组中的分布并不是随机的。不同重复拷贝类别在基因组中存在种属间和碱基组成的特异性,各种优势的重复序列类型不同。此外,基因中在编码区和非编码区的分布也表现出种属和碱基组成差异。这种差异显示了微卫星序列起源进化的复杂性,也反映了基因中微卫星序列的生物学功能。功能基因为遗传学工作者提供了一个联系表型和基因型的手段,研究功能基因中的微卫星序列不仅在绘制精细遗传图谱、筛选重要农艺性状基因、物种进化等问题上都有着重要的作用,而且在疾病治疗有潜在的应用价值。本文主要阐述了微卫星序列的形成机制、基因中微卫星序列的分布以及功能基因中微卫星序列的生物学作用,并指出了目前实践中的一些问题。

The Development of the Microsatellitics in the Functional Genes

Microsatellitic distributes widely in the genome of eukaryotes and some prokaryotes, but not stochastic. Both the abundance and distribution characteristics of repeat types, such as dinucleotide repeats and trinucleotide repeats are varied in different or- ganisms and the variedness also occurs in different repeat classes between coding regions and non-coding regions. All of the above diffe-r ences indicate that the genesis and evolution of microsatellitic are complex and may have several typical biology functions. Functional gene offers a useful means for geneticists' researchers to associate the phenotype and the various genotypes. The microsatellitic in the functional genes is not only used for linkage maps, some important gene selecting, and some problems of the plants evolution, but also used for the potential application to cure correlative diseases. This paper elucidates the mechanism of the microsatellitics, the distribution characteristics of repeat types in different regions of gene, and the signification of the SSR in the functional genes. Some difficulties in the application are also elucidated.