Population genomic analyses confirm male-biased mutation rates in snakes
Population genomic analyses confirm male-biased mutation rates in snakes
复制标题
群体基因组分析证实蛇的雄性突变率
DOI：
10.1093/jhered/esab005
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发表时间：
2021
影响因子：
3.1
通讯作者：
Castoe, Todd A
中科院分区：
文献类型：
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作者：
Schield, Drew R;Perry, Blair W;Nikolakis, Zachary L;Mackessy, Stephen P;Castoe, Todd A
雄性偏向的突变率发生在各种生物体中。男女突变率的比例可能对整个基因组的进化产生重大影响，特别是对性连锁基因。在ZW物种中，Z染色体三分之二的时间由男性携带，导致预测男性偏向的突变率将对Z连锁基因相对于常染色体和W染色体的进化产生不成比例的影响。Colubroid蛇（包括colubrids，elapids和viperids）具有ZW性别决定，但男性偏向的突变率尚未在这组中得到很好的研究。在这里，我们分析了响尾蛇的种群基因组数据集，以量化物种内的遗传变异和物种间的遗传差异。我们使用一种新的方法，无偏估计的人口遗传汇总统计量，比较Z染色体和常染色体之间的变化，并计算净核苷酸物种之间的差异。我们发现雄性响尾蛇的突变率是雌性的2.03倍，对应的平均μZ/μ A比率为1.1。我们从蛇的结果在数量上与鸟类相似，这表明雄性偏向的突变率可能是ZW性别决定的脊椎动物谱系的共同特征。
Male-biased mutation rates occur in a diverse array of organisms. The ratio of male-to-female mutation rate may have major ramifications for evolution across the genome, and for sex-linked genes in particular. In ZW species, the Z chromosome is carried by males two-thirds of the time, leading to the prediction that male-biased mutation rates will have a disproportionate effect on the evolution of Z-linked genes relative to autosomes and the W chromosome. Colubroid snakes (including colubrids, elapids, and viperids) have ZW sex determination, yet male-biased mutation rates have not been well studied in this group. Here we analyze a population genomic dataset from rattlesnakes to quantify genetic variation within and genetic divergence between species. We use a new method for unbiased estimation of population genetic summary statistics to compare variation between the Z chromosome and autosomes and to calculate net nucleotide differentiation between species. We find evidence for a 2.03-fold greater mutation rate in male rattlesnakes relative to females, corresponding to an averageμZ/μAratio of 1.1. Our results from snakes are quantitatively similar to birds, suggesting that male-biased mutation rates may be a common feature across vertebrate lineages with ZW sex determination.