Genetic diversity and relationship of Dulong chickens using mitochondrial DNA control region

Abstract

The genetic structure and evolutionary relationship of Dulong chicken with other native Chinese species remained unclear. In this study, the mitochondrial control region was analyzed in total of 343 samples comprising 59 from Dulong chicken and 284 from 8 other Chinese local breeds revealed 51 mutation sites that defined 42 haplotypes. The maximum genetic variation was observed between the Shimian caoke and Pengxian yellow chickens. Phylogenetic analysis revealed that these local chickens mainly scatter in two southwestern clades. Dulong chickens have close relationship with other native chicken. Finding of this study suggests a single matrilineal lineage of indigenous Dulong chickens.

Keywords: Dulong chicken; Genetic diversity; mitochondrial DNA.

Figure 1.

Evolutionary relationship of all chicken samples. Note. the image on the left: evolutionary relationship of 42 unique partial control region sequences from 343 chickens constructed using the neighbor-joining model with the p-distance method. The reliability of the estimated trees was evaluated by the bootstrap method with 1000 replications. Only bootstrap values more than 50% are shown in this figure. The image on the right: maximum parsimony median-joining network of Dulong chickens with other Sichuan local chicken breeds based on 482 bp control region sequence. Node sizes are proportional to haplotype frequencies. The lines linking the nodes are proportional to the mutation steps. Red nodes (mv1–mv7) indicate inferred steps not identified in the sampled populations. Colors within the circles represent chickens different localities at which each haplotype was detected.