Genetic diversity and population structure of black Dahe pig based on DNA sequences analyses of mitochondrial and nuclear genes

摘要

To investigate the genetic diversity and population structure of black Dahe pigs, we collected 175 samples from 5 local populations and sequenced them using a combination of two selected molecular markers for mitochondrial cytochrome b and Major Histocompatibility Complex (MHC) DRB. Overall, the results of AMOVA and phylogenetic tree and gene flow analyses detected high levels of gene flow among the five populations, particularly individual pigs from Dahe town (PopD or Yingshang town (Pop2) to otherpopulations (Pop3, Pop4, and Pop5). The genetic diversity analyses showed that the diversity indices of the five populations did not vary significantly, but they were much lower than those of other Chinese pig species. These results suggest that distinctgene flow, unstable population pattern, and lower genetic diversity have been influenced mainly by human introductions for economic ends. These findings provide genetic information that could be used for the preservation and further genetic improvementof the black Dahe pig, as well as an important reference for the evaluation, conservation, and utilization of the genetic resources of this breed.