Marais Gabriel
Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh EH9 3JT, Scotland, UK.
Trends Genet. 2003 Jun;19(6):330-8. doi: 10.1016/S0168-9525(03)00116-1.
Classical genetic studies show that gene conversion can favour some alleles over others. Molecular experiments suggest that gene conversion could favour GC over AT basepairs, leading to the concept of biased gene conversion towards GC (BGC(GC)). The expected consequence of such a process is the GC-enrichment of DNA sequences under gene conversion. Recent genomic work suggests that BGC(GC) affects the base composition of yeast, invertebrate and mammalian genomes. Hypotheses for the mechanisms and evolutionary origin of such a strange phenomenon have been proposed. Most BGC(GC) events probably occur during meiosis, which has implications for our understanding of the evolution of sex and recombination.
经典遗传学研究表明，基因转换对某些等位基因的青睐程度可能高于其他等位基因。分子实验表明，基因转换可能更倾向于GC碱基对而非AT碱基对，从而引出了向GC（BGC(GC)）偏向性基因转换的概念。这一过程的预期结果是基因转换作用下DNA序列的GC富集。近期的基因组研究表明，BGC(GC)会影响酵母、无脊椎动物和哺乳动物基因组的碱基组成。针对这一奇特现象的机制和进化起源，人们已经提出了各种假说。大多数BGC(GC)事件可能发生在减数分裂期间，这对我们理解性别和重组的进化具有重要意义。
