Correlation between GHR gene polymorphism and growth traits in Qinghai plateau yaks.

[Objective] This study explored the relationship between GHR gene polymorphism and growth traits of Qinghai plateau yaks. [Method] The GHR gene was amplified by PCR in a test population f 440 healthy yaks at the ages of 30-36 months under same grazing conditions, before being sequenced and analyzed for SNPs using DNASTAR 7.1 software. The association between different genotypes and heir combined genotypes with growth and development indicators (body mass, body height, body slope ength, chest circumference and tube circumference) was then analyzed. [Result] Three SNPs of g. 732091C>G, g. 732195A>G and g. 732373G>A existed on the GHR gene of Qinghai plateau yaks, where two genotypes (AA and AG ) presented on g. 732195A>G and three genotypes presented on g. 732091OGCCC, CG and GG) and g. 732373G > A (GA, AA and GG). The χ² test showed that g. 732091C>G, g. 732195A>G and g. 732373G>A were in Hardy-Weinberg extreme imbalance, g. 732195A>G was low polymorphic (PIC<0.25), g. 732091OG and g. 732373G>A were moderately polymorphic (0.25<PIC<0.50). The association analysis with growth traits revealed that g. 732091C>G, g. 732195A>G and g. 732373G>A could significantly or highly significantly affect body weight and chest circumference in lateau yaks, and the dominant genotype was GG for g. 732091 OG and g. 732373G> A and A A for g. 732195A>G. The combined genotype GG-AA-GG individuals showed the best growth and development, specially in body slope length. [Conclusion] There were three SNPs in the GHR gene of Qinghai plateau yaks. Because of the association with some growth traits, it could be used as candidate genes for molecular marker-assisted selection in yaks. [ABSTRACT FROM AUTHOR]