Lack of nucleotide polymorphism in the Y-linked sperm flagellar dynein gene Dhc-Yh3 of Drosophila melanogaster and D. simulans.
Lack of nucleotide polymorphism in the Y-linked sperm flagellar dynein gene Dhc-Yh3 of Drosophila melanogaster and D. simulans.
复制标题
黑腹果蝇和模拟果蝇的 Y 连锁精子鞭毛动力蛋白基因 Dhc-Yh3 缺乏核苷酸多态性。
DOI：
10.1093/genetics/153.4.1709
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发表时间：
1999
期刊：
影响因子：
3.3
通讯作者：
Eanes,WF
中科院分区：
文献类型：
--
作者：
Zurovcova,M;Eanes,WF
我们研究了黑腹果蝇亚组的5个成员中与Y连锁基因相关的种内和种间核苷酸变异水平。利用已发表的Dhc-Yh 3基因的348 bp序列，以及根据海胆和衣原体鞭毛动力蛋白基因的比较设计的简并PCR引物，我们在D.黑腹菌对世界范围内收集的11个D. melanogaster和D. simulans在后一种物种中只发现了一种沉默的多态性。Dhc-Yh 3的每个位点的同义位点差异与X和常染色体基因的值相当。假设采用Wright-Fisher群体模型，使用适当降低的X和常染色体θ估计值，缺乏变异在统计学上小于预期。由于Y染色体只编码六个已知基因，与背景选择相关的遗传搭便车不太可能解释这种低变异。相反，与性别比例染色体相关的适应性搭便车，或男性生育力的大变化可能会减少Y染色体上的多态性。密码子偏好性非常低，如在低重组区域中的其他基因所见。
We studied levels of intra- and interspecific nucleotide variation associated with a Y-linked gene in five members of the Drosophila melanogaster subgroup. Using published sequence for 348 bp of the Dhc-Yh3 gene, and degenerate PCR primers designed from comparisons of the sea urchin and Chlamydomonas flagellar dynein genes, we recovered a 1738-bp region in D. melanogaster. Analyses of sequence variation in a worldwide collection of 11 lines of D. melanogaster and 10 lines of D. simulans found only a single silent polymorphism in the latter species. The synonymous site divergence per site for Dhc-Yh3 is comparable to values for X and autosomal genes. Assuming a Wright-Fisher population model, the lack of variation is statistically less than expected using appropriately reduced estimates of θ from the X and autosomes. Because the Y chromosome encodes only six known genes, genetic hitchhiking associated with background selection is unlikely to explain this low variation. Conversely, adaptive hitchhiking, as associated with sex-ratio chromosomes, or a large variance in male fertility may reduce the polymorphism on the Y chromosome. Codon bias is very low, as seen for other genes in regions of low recombination.