秦川牛 MYH8基因多态性及其与生长性状的关联分析
Polymorphism in MYH8 Gene and Association with Growth Traits of Qinchuan Beef Cattle

为研究秦川牛MYH8基因的多态性及其与秦川牛生长性状的关联性，选取163头健康的30月± 2月龄 秦川牛，采用DNA测序技术发现MYH8基因外显子上的SNP位点，并以PCR RFLP技术分析秦川牛群MYH8基因型，研究其遗传多样性，再通过SPSS 19.0软件分析SNP位点与秦川牛体尺性状和胴体性状的关联性。研究结果表明，在MYH8基因第33外显子上存在3个SNP位点，分别在基因序列26 064、26 094和 26 100 bp 3处，且26 064 bp处（T>C）为同义突变，26 094 bp处（T>C）为错义突变，26 100 bp处（C>G）为错义突变。关联分析显示， C26100G突变发生在体斜长指标，表现为GG基因型个体的群体均值显著高于GC、CC基因型个体（P<0.05）；而其他突变中不存在显著性差异。某些基因型（T26064C突变处TC基因型和T26094C突变处CT基因型）可能为优势基因型，但还需通过更多个体验证。说明：MYH8基因对秦川肉牛生长性状存在一定影响。
The aim of the study is to research polymorphism of MYH8 and its association with growth traits of Qinchuan beef cattle,and to provide a theoretical basis for the improvement of Qinchuan beef cattle. 163 Qinchuan cattle were used to detected polymorphism of MYH8 by means of DNA sequencing and PCR RFLP. The association analysis was conducted between MYH8 gene and growth and carcass traits of Qinchuan cattle with SPSS 19.0 software. The results showed that three SNPs,including one synonymous mutation at 26 064(T>C),two mis sense mutations at 26 094 (T>C) and 26 100 (C>G) respectively,were detected in Exon 33 of MYH8 gene. The association analysis indicated that only GG genotype at 26 100 (C>G) had longer body length than GC and CC genotypes,no significant association was detected between other genotypes and growth traits,however,some genotypes tend to have better performance,namely TC genotype at 26 064 (T>C) and CT genotype at 26 094 (T>C),further analysis in larger group may be helpful to classified.The result showed that MYH8 had effect on growth traits in Qinchuan beef cattle.