关键词: 三穗鸭, 全基因组关联分析, 体尺性状, 屠宰性状, 候选基因

Abstract: To screen out the genetic loci and functional genes affecting the body size and slaughter traits of Sansui ducks，655 160‐day‐old Sansui ducks were taken as the research subjects，and the phenotypic data such as body size（body skew length，neck length）and slaughter traits（pre‐slaughter live weight，carcass weight，evisceration weight and chest and leg muscle rate）were measured.The individual single nucleotide polymorphism（SNP）genotypes were obtained by genome‐wide association study（10×depth），quality control analysis was conducted based on PLINK 1.9，mixed linear model association analysis was performed using GEMMA，the KEGG candidate gene function enrichment analysis of the significant association sites was performed by clusterProfiler.The results showed a total of 207，78，64，66，68 and 96 SNP loci significantly associated with body skew length，neck length，pre‐slaughter live weight，carcass weight，evisceration weight and chest and leg muscle rate，and 50，31，32，40，27 and 37 candidate genes annotated respectively.The results of KEGG enrichment analysis showed that 16，10，12，11，13 and 22 KEGG pathways were enriched for candidate genes related to body skew length，neck length，pre‐slaughter live weight，carcass weight，evisceration weight and chest and leg muscle rate.Neuroactive ligand‐receptor interaction was associated with all six traits，the calcium signaling pathway was associated with body skew length，carcass weight，eviscerated weight，and chest and leg muscle rate，and MAPK signaling pathway was associated with pre‐slaughter live weight，carcass weight，eviscerated weight.LOC119717855，GPR50，GRM7，GABRB2，GABRG2 and LOC101800857 were identified as key candidate genes for body skew length，while GRIK2 and BNIP1 were identified as key candidate genes for neck length.TAF2 and NPK genes were identified as the key candidate genes for pre‐slaughter live weight，carcass weight and evisceration weight traits. SLC8A1 gene was identified as key candidate gene for carcass weight and evisceration weight，HTR2A，QRFPR，NPVF and UTS2R genes were identified as the key candidate genes for chest and leg muscle rate.The above results showed that key signaling pathways such as neuroactive ligand‐receptor interaction and calcium signaling pathway，as well as key candidate genes such as LOC119717855，GPR50，GRIK2 and TAF2，which affected the body size and slaughter traits of Sansui ducks，were screened.

Key words: Sansui duck, Genome‐wide association study, Body size trait, Slaughter trait, Candidate gene