Growth traits is a critical economic trait for animal husbandry. In this study, the SNPs of CTNNA3 and CAP2 genes were investigated to check whether they are associated with growth traits (body weight, body height, body length and chest circumference) in Hu sheep. The result of the association analysis indicated that the mutation in CTNNA3 (g.2018018 A > G) were associated significantly with body weight, body height, body length and chest circumference (P < 0.05), the mutation in CAP2 (g.8588 T > C) were associated significantly with body height at 140, 160, 180 days (P < 0.05), AA and CC of CTNNA3 and CAP2 were the dominant genotypes associated with growth traits in Hu sheep. Moreover, combined effect analyses indicated that the growth traits with combined genotypes AA^CTNNA3-CC^CAP2 and AA^CTNNA3-CT^CAP2 were higher than those with genotype GG^CTNNA3-CT^CAP2. RT-qPCR indicated that CTNNA3 expression levels were significantly higher in liver and lung than in other nine tissues (P < 0.05), CAP2 expression levels were significantly higher in bone, heart, liver, lung and duodenum than in other six tissues (P < 0.05). In conclusion, CTNNA3 and CAP2 polymorphisms could be used as genetic markers for improving growth traits in Hu sheep husbandry.

生长性状是畜牧业的重要经济性状。本研究对CTNNA3和CAP2基因的SNP进行了研究，以检查它们是否与胡羊的生长性状（体重、身高、体长和胸围）相关。关联分析结果表明CTNNA3突变（g.2018018 A > G）与体重、身高、体长和胸围显着相关（P  < 0.05），CAP2突变（g.8588 T > C）在140，160，180天（与身体高度显著相关联P  <0.05），AA和CC的CTNNA3和CAP2是与胡羊生长性状相关的优势基因型。此外，组合的效果分析表明，生长性状与结合基因型AA ^CTNNA3 -CC ^CAP2和AA ^CTNNA3 -CT ^CAP2均较与基因型GG更高^CTNNA3 -CT ^CAP2。RT-qPCR显示CTNNA3在肝脏和肺中的表达水平显着高于其他9种组织（P  < 0.05），CAP2在骨、心脏、肝脏、肺和十二指肠中的表达水平显着高于其他6种组织（P  < 0.05）。0.05）。总之，CTNNA3和CAP2多态性可作为改善胡羊养殖生长性状的遗传标记。