Emerson J J, Cardoso-Moreira Margarida, Borevitz Justin O, Long Manyuan
Department of Ecology and Evolution, University of Chicago, Chicago, IL 60637, USA.
Science. 2008 Jun 20;320(5883):1629-31. doi: 10.1126/science.1158078. Epub 2008 Jun 5.
The role that natural selection plays in governing the locations and early evolution of copy-number mutations remains largely unexplored. We used high-density full-genome tiling arrays to create a fine-scale genomic map of copy-number polymorphisms (CNPs) in Drosophila melanogaster. We inferred a total of 2658 independent CNPs, 56% of which overlap genes. These include CNPs that are likely to be under positive selection, most notably high-frequency duplications encompassing toxin-response genes. The locations and frequencies of CNPs are strongly shaped by purifying selection, with deletions under stronger purifying selection than duplications. Among duplications, those overlapping exons or introns, as well as those falling on the X chromosome, seem to be subject to stronger purifying selection.
自然选择在控制拷贝数突变的位置和早期进化中所起的作用在很大程度上仍未得到探索。我们使用高密度全基因组平铺阵列创建了黑腹果蝇拷贝数多态性（CNP）的精细基因组图谱。我们推断出总共2658个独立的CNP，其中56%与基因重叠。这些包括可能处于正选择下的CNP，最显著的是包含毒素反应基因的高频重复。CNP的位置和频率受到纯化选择的强烈影响，缺失受到的纯化选择比重复更强。在重复中，那些与外显子或内含子重叠的重复，以及那些位于X染色体上的重复，似乎受到更强的纯化选择。
