Objective

Min pigs are a unique genetic resource among local pig breeds in China. They have more excellent characteristics in cold and stress resistance, good meat quality, and a high reproductive rate. However, the genetic structure and driving factors remain unclear in the nucleus herd. In this study, the genetic diversity of Min pigs was studied to reveal the formation mechanism of its unique genetic structure. We hope to protect and develop the genetic resources of Min pigs.

Methods

We analyzed different types of genes to identify the genetic structure and gene introgression pattern of Min pigs. The nuclear DNA dataset includes information on 21 microsatellite loci and 6 Y-chromosome genes, and the mitochondrial D-loop gene is selected to represent maternal lineages. The above genes are all from the nucleus herd of Min pigs.

Results

The results of genetic structure identification and analysis of potential exogenous gene introgression patterns indicate that the nucleus herd of Min pigs maintains a high level of genetic diversity (polymorphism information content = 0.713, expected heterozygosity = 0.662, observed heterozygosity = 0.612). Compared with other Asian pig breeds, the formation of Min pig breeds is more special. Gene introgression from European pig breeds to Min pigs has occurred, which is characterized by complete introgression of paternal genes and incomplete introgression of maternal genes.

Conclusion

Gene introgression caused by cross-breeding is not the main factor leading to the formation of the current genetic structure of Min pigs, but this process has increased the level of genetic diversity in the nucleus herd. Compared with the influence of gene introgression, our research suggest that artificial selection and environmental adaptive evolution make Min pigs form unique genetic characteristics.

中文翻译：

---

群体遗传学揭示了小型猪核心群中的新基因渗入

客观的

闽猪是我国地方猪种中独特的遗传资源。具有更加优良的抗寒、抗逆、肉质好、繁殖率高等特点。然而，核心群体的遗传结构和驱动因素仍不清楚。本研究对闽猪遗传多样性进行研究，揭示其独特遗传结构的形成机制。我们希望保护和开发闽猪遗传资源。

方法

我们分析了不同类型的基因，以确定闽猪的遗传结构和基因渗入模式。核DNA数据集包括21个微卫星位点和6个Y染色体基因的信息，并选择线粒体D环基因来代表母系谱系。上述基因均来自闽猪核心群。

结果

遗传结构鉴定和潜在外源基因渗入模式分析结果表明，闽猪核心群保持了较高水平的遗传多样性（多态性信息含量=0.713，期望杂合度=0.662，观察杂合度=0.612）。与其他亚洲猪品种相比，闽猪品种的形成较为特殊。欧洲猪种向闽猪发生了基因渗入，其特点是父系基因完全渗入，母系基因不完全渗入。

结论

杂交产生的基因渗入并不是导致闽猪目前遗传结构形成的主要因素，但这一过程提高了核心猪群的遗传多样性水平。与基因渗入的影响相比，我们的研究认为，人工选择和环境适应性进化使闽猪形成了独特的遗传特征。