Palsson Arnar, Rouse Ann, Riley-Berger Rebecca, Dworkin Ian, Gibson Greg
Department of Genetics, North Carolina State University, Raleigh, North Carolina 27513-7614, USA.
Genetics. 2004 Jul;167(3):1199-212. doi: 10.1534/genetics.104.026252.
The Epidermal growth factor receptor is an essential gene with diverse pleiotropic roles in development throughout the animal kingdom. Analysis of sequence diversity in 10.9 kb covering the complete coding region and 6.4 kb of potential regulatory regions in a sample of 250 alleles from three populations of Drosophila melanogaster suggests that the intensity of different population genetic forces varies along the locus. A total of 238 independent common SNPs and 20 indel polymorphisms were detected, with just six common replacements affecting >1475 amino acids, four of which are in the short alternate first exon. Sequence diversity is lowest in a 2-kb portion of intron 2, which is also highly conserved in comparison with D. simulans and D. pseudoobscura. Linkage disequilibrium decays to background levels within 500 bp of most sites, so haplotypes are generally restricted to up to 5 polymorphisms. The two North American samples from North Carolina and California have diverged in allele frequency at a handful of individual SNPs, but a Kenyan sample is both more divergent and more polymorphic. The effect of sample size on inference of the roles of population structure, uneven recombination, and weak selection in patterning nucleotide variation in the locus is discussed.
表皮生长因子受体是一个重要基因，在整个动物界的发育过程中具有多种多效性作用。对来自黑腹果蝇三个种群的250个等位基因样本中覆盖完整编码区的10.9 kb和潜在调控区的6.4 kb序列多样性进行分析，结果表明不同群体遗传力的强度沿基因座变化。共检测到238个独立的常见单核苷酸多态性（SNP）和20个插入缺失多态性，仅有6个常见替换影响超过1475个氨基酸，其中4个位于较短的可变第一外显子中。内含子2的2 kb区域内序列多样性最低，与拟果蝇和伪暗果蝇相比，该区域也高度保守。在大多数位点的500 bp范围内，连锁不平衡衰减至背景水平，因此单倍型通常限制在最多5个多态性。来自北卡罗来纳州和加利福尼亚州的两个北美样本在少数几个单核苷酸多态性位点的等位基因频率上存在差异，但肯尼亚样本的差异更大且多态性更高。讨论了样本量对推断群体结构、不均匀重组和弱选择在该基因座核苷酸变异模式中的作用的影响。
