Laboratory for Conservation and Utilization of Bio-resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, China.
Heredity (Edinb). 2010 Sep;105(3):274-81. doi: 10.1038/hdy.2009.191. Epub 2010 Feb 24.
Black coat colour is common in Chinese indigenous domestic pigs, but not among their wild ancestors, and it is thus presumed to be a 'domestication trait.' To determine whether artificial interference contributes to morphological diversification, we examined nucleotide variation from 157 Chinese domestic pigs and 40 wild boars in the melanocortin receptor 1 (MC1R) gene, which has a key role in the coat pigmentation of Sus scrofa. Compared with a pseudogene GPIP, our results showed that the joint effects of demography and selection have resulted in markedly low genetic diversity of MC1R in Chinese domestic pigs. Coalescent simulation and selection tests further suggest that the fixation of two non-synonymous substitutions associated with black colour is the result of artificial selection. In contrast, a much higher genetic diversity and only a single non-synonymous substitution were found among the wild boars, suggesting a strong functional constraint. Moreover, our conclusion is consistent with the preference for black colour in the ancient Chinese sacrificial culture. This case provides an interesting example of a molecular evaluation of artificial livestock selection and its associated cultural impact in ancient China.
黑色皮毛是中国本土家猪的常见特征，但在它们的野生祖先中并不存在，因此黑色被认为是一种“驯化特征”。为了确定人工干预是否有助于形态多样化，我们检测了黑素皮质素受体 1（MC1R）基因中的核苷酸变异，该基因在家猪的皮毛颜色形成中起着关键作用。与假基因 GPIP 相比，我们的结果表明，人口统计学和选择的共同作用导致了中国本土家猪 MC1R 基因显著的低遗传多样性。合并模拟和选择测试进一步表明，与黑色相关的两个非同义突变的固定是人工选择的结果。相比之下，野猪的遗传多样性要高得多，只发现了一个非同义突变，这表明存在强烈的功能约束。此外，我们的结论与中国古代祭祀文化中对黑色的偏好是一致的。这个例子为中国古代人工选择家畜及其相关文化影响的分子评估提供了一个有趣的案例。
