title: Genome-Wide Association Studies for Comb Traits in Chickens.
abstract: The comb, as a secondary sexual character, is an important trait in chicken. Indicators of comb length (CL), comb height (CH), and comb weight (CW) are often selected in production. DNA-based marker-assisted selection could help chicken breeders to accelerate genetic improvement for comb or related economic characters by early selection. Although a number of quantitative trait loci (QTL) and candidate genes have been identified with advances in molecular genetics, candidate genes underlying comb traits are limited. The aim of the study was to use genome-wide association (GWA) studies by 600 K Affymetrix chicken SNP arrays to detect genes that are related to comb, using an F2 resource population. For all comb characters, comb exhibited high SNP-based heritability estimates (0.61-0.69). Chromosome 1 explained 20.80% genetic variance, while chromosome 4 explained 6.89%. Independent univariate genome-wide screens for each character identified 127, 197, and 268 novel significant SNPs with CL, CH, and CW, respectively. Three candidate genes, VPS36, AR, and WNT11B, were determined to have a plausible function in all comb characters. These genes are important to the initiation of follicle development, gonadal growth, and dermal development, respectively. The current study provides the first GWA analysis for comb traits. Identification of the genetic basis as well as promising candidate genes will help us understand the underlying genetic architecture of comb development and has practical significance in breeding programs for the selection of comb as an index for sexual maturity or reproduction.
authors.affiliation: Layer Breeding and Production, Jiangsu Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, China.
authors.forename: Manman
authors.initials: M
authors.lastname: Shen
authors.affiliation: Layer Breeding and Production, Jiangsu Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Qu
authors.affiliation: Layer Breeding and Production, Jiangsu Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Ma
authors.affiliation: Layer Breeding and Production, Jiangsu Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, China.
authors.forename: Taocun
authors.initials: T
authors.lastname: Dou
authors.affiliation: Layer Breeding and Production, Jiangsu Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Lu
authors.affiliation: Layer Breeding and Production, Jiangsu Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Guo
authors.affiliation: Layer Breeding and Production, Jiangsu Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, China.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Hu
authors.affiliation: National Engineering Laboratory for Animal Breeding and MOA Key Laboratory of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China.
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Yi
authors.affiliation: National Engineering Laboratory for Animal Breeding and MOA Key Laboratory of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China.
authors.forename: Jingwei
authors.initials: J
authors.lastname: Yuan
authors.affiliation: National Engineering Laboratory for Animal Breeding and MOA Key Laboratory of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China.
authors.forename: Congjiao
authors.initials: C
authors.lastname: Sun
authors.affiliation: Layer Breeding and Production, Jiangsu Institute of Poultry Science, Chinese Academy of Agricultural Science, Yangzhou, China.
authors.forename: Kehua
authors.initials: K
authors.lastname: Wang
authors.affiliation: National Engineering Laboratory for Animal Breeding and MOA Key Laboratory of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Yang
mesh_terms: D000483:Alleles; D000818:Animals; D001947:Breeding; D002645:Chickens / Q000235:genetics* / Q000502:physiology; D005260:Female; D014644:Genetic Variation; D055106:Genome-Wide Association Study; D005838:Genotype; D008297:Male; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D012741:Sexual Maturation