Distribution of dinucleotide microsatellites in the Drosophila melanogaster genome
Distribution of dinucleotide microsatellites in the Drosophila melanogaster genome
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DOI：
10.1093/oxfordjournals.molbev.a026142
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发表时间：
1999-05-01
影响因子：
10.7
通讯作者：
Schlötterer, C
中科院分区：
文献类型：
--
作者：
Bachtrog, D;Weiss, S;Schlötterer, C
微卫星是一类特殊的重复DNA，已成为最常用的遗传标记之一。各种基因组计划的进展使得研究微卫星的基因组分布和评估几个参数对其发生的潜在影响成为可能。本文报道了二核苷酸微卫星在果蝇基因组中的分布。当仅考虑含有5个或多个重复单元的微卫星时，D. melanogaster为6.7个重复。我们测试了广泛的参数，可能会影响微卫星密度，我们没有检测到重组率，外显子的数量，或编码序列的总长度的显着影响。与微卫星起源的中性预期一致。AT含量与（AT/TA）（n）微卫星密度呈显著正相关。虽然这种模式可能表明，微卫星的起源是一个随机的过程，我们也发现了微卫星的非随机分布的证据。平均微卫星密度较高的X染色体，但极端异质性观察不同的基因组区域之间。微卫星的这种聚集在局部范围内也很明显，因为分析的连续序列中有38.9%显示出与微卫星随机分布的偏差。
Microsatellites, a special class of repetitive DNA, have become one of the most popular genetic markers. The progress of various genome projects has made it possible to study the genomic distribution of microsatellites and to evaluate the potential influence of several parameters on their genesis. We report the distribution of dinucleotide microsatellites in the genome of Drosophila melanogaster. When considering only microsatellites with five or mure repeat units, the average length of dinucleotide repeats in D. melanogaster is 6.7 repeats. We tested a wide range of parameters which could potentially influence microsatellite density, and we did not detect a significant influence of recombination rate, number of exons, or total length of coding sequence. In concordance with the neutral expectation for the origin of microsatellites. a significant positive correlation between AT content and (AT/TA)(n) microsatellite density was detected. While this pattern may indicate that microsatellite genesis is a random process, we also found evidence for a nonrandom distribution of microsatellites. Average microsatellite density was higher on the X chromosome, but extreme heterogeneity was observed between different genomic regions. Such a clumping of microsatellites was also evident on a more local scale, as 38.9% of the contiguous sequences analyzed showed a deviation from a random distribution of microsatellites.