The domestication of animals is very important in human history, which has led to the transformation of human life from hunting and gathering to an agricultural lifestyle. As one of the most important livestock, pigs were domesticated in multiple locations approximately 9,000 years ago (Giuffra et al., 2000; Larson et al., 2005), leading to a series of changes involving behavior, morphology, and physiology (Groenen, 2016; Larson & Burger, 2013; Ramos-Onsins, Burgos-Paz, Manunza, & Amills, 2014). And then, artificial selection has been conducted to improve agriculturally important traits, which not only further results in population diversity, but also makes a few similar characters of the populations with the same breeding objectives, such as growth rate and dietary habits