A significant genomic region underlying growth traits in adult Beijing You chicken identified by genome-wide association analysis

As a Chinese indigenous chicken breed, Beijing You Chicken is renowned for its high-quality meat and eggs, as well as distinctive morphological features including feathered shanks, beards, and crests. In this study, in order to understand the genetic basis for growth traits of this breed, we performed genome-level analysis for body weight and related morphometric phenotypes in Beijing You Chicken. Totally, we selected 224 adult female individuals at 38 weeks to measure growth traits including body weight, tibia length, and shoulder width. Whole-genome sequencing was performed on all samples, followed by genome-wide association studies (GWAS) in order to identify candidate genes and genomic regions associated with these traits. The results showed that one genomic region on chromosome 4, harboring six genes including NCAPG, KCNIP4, SLIT2, LCORL, CLRN2, and LDB2, was significantly associated with body weight and other related growth traits. Our findings revealed a strong association between these SNPs (single nucleotide polymorphisms) and body size traits, providing critical insights into the genetic basis of body weight traits in Beijing You Chicken and the SNPs could be furtherly applied to marker assistant selection for body weight trait in the local chickens.