Whole-genome resequencing reveals genetic characteristics of different duck breeds from the Guangxi region in China.

Distinctive indigenous duck (Anas platyrhynchos) populations of Guangxi, China, evolved due to the geographical, cultural, and environmental variability of this region. To investigate the genetic diversity and population structure of the indigenous ducks of Guangxi, 78 individuals from eight populations were collected and sequenced by whole-genome resequencing with an average depth of ∼9.40×. The eight indigenous duck populations included four breeds and four resource populations. Moreover, the genome data of 47 individuals from two typical meat-type breeds and two native egg-type breeds were obtained from a public database. Calculation of heterozygosity, nucleotide diversity (π), Tajima's D, and FST indicated that the Guangxi populations were characterized by higher genetic diversity and lower differentiation than meat-type breeds. The highest diversity was observed in the Xilin-Ma ducks. Principal component, structure, and phylogenetic tree analyses revealed the relationship between the indigenous duck populations of Guangxi. A mild degree of differentiation was observed among the Guangxi populations, although three populations were closer to the meat or egg breeds. Indigenous populations are famous for their special flavor, small body size, and slow growth rates. Selective sweep analysis revealed the candidate genes and pathways associated with these growth traits. Our findings provide a valuable source of information regarding genetic diversity, population conservation, and genome-associated breeding of ducks.