Zhang Li, Ma Xiaomeng, Xuan Junli, Wang Huihua, Yuan Zehu, Wu Mingming, Liu Ruizao, Zhu Caiye, Wei Caihong, Zhao Fuping, Du Lixin
Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
PLoS One. 2016 Jul 29;11(7):e0159504. doi: 10.1371/journal.pone.0159504. eCollection 2016.
2 SNPs were discovered in our previous genome-wide association study (GWAS): s58995.1 (rs420767326 A>G) in MEF2B gene and OAR3_115712045.1 (rs401775061 A>C) in TRHDE gene, which were significantly associated with post-weaning gain in sheep. Herein, we performed a replication experiment to investigate single nucleotide polymorphisms (SNPs) within the MEF2B and TRHDE gene exons, the 5'untranslated regions (within 1000bp), the 3' untranslated regions (within 1000bp) and their associations with Ujumqin sheep growth traits in 4-month age and 6-month age, respectively. Finally,3 SNPs were selected to be investigated including 1 SNP in 3'untranslated regions in MEF2B gene (rs417014745 A>G) and 2 SNPs in TRHDE gene (rs426980328 T>C and rs430810656 G>A).The χ2 test showed all the 3 variations were in Hardy-Weinberg equilibrium (P>0.05) status. Association analysis suggested that rs426980328 T>C was significantly associated with body weight and chest girth in 4-month age (P<0.05). rs430810656 G>A exhibited extremely significant association with body weight and chest girth in 4-month age (P<0.01). rs417014745 A>G was extremely significantly associated with body weight and chest girth in 4-month age and chest girth in 6-month age (P<0.01), and it was also significantly associated with body weight in 6-month age (P<0.05). Combined effect analysis indicated significant associations between the combinations of rs426980328-rs417014745, rs430810656-rs417014745 and several growth traits (P<0.05). These results suggested MEF2B and TRHDE genes affected growth traits in Ujumqin sheep and the combination effect of the two genes also played a significant effective role. These SNPs might have potential value as genetic markers for growth traits and it could be used in Ujumqin sheep breeding in future. Further studies are necessary to confirm our findings.
在我们之前的全基因组关联研究（GWAS）中发现了2个单核苷酸多态性（SNP）：MEF2B基因中的s58995.1（rs420767326 A>G）和TRHDE基因中的OAR3_115712045.1（rs401775061 A>C），它们与绵羊断奶后增重显著相关。在此，我们进行了一项重复实验，以研究MEF2B和TRHDE基因外显子、5'非翻译区（1000bp内）、3'非翻译区（1000bp内）的单核苷酸多态性（SNP），以及它们分别与4月龄和6月龄乌珠穆沁羊生长性状的关联。最后，选择了3个SNP进行研究，包括MEF2B基因3'非翻译区的1个SNP（rs417014745 A>G）和TRHDE基因的2个SNP（rs426980328 T>C和rs430810656 G>A）。χ2检验表明，所有3个变异均处于哈迪-温伯格平衡（P>0.05）状态。关联分析表明，rs426980328 T>C与4月龄时的体重和胸围显著相关（P<0.05）。rs430810656 G>A与4月龄时的体重和胸围呈极显著关联（P<0.01）。rs417014745 A>G与4月龄时的体重和胸围以及6月龄时的胸围呈极显著关联（P<0.01），并且与6月龄时的体重也显著相关（P<0.05）。联合效应分析表明，rs426980328 - rs417014745、rs430810656 - rs417014745的组合与几个生长性状之间存在显著关联（P<0.05）。这些结果表明，MEF2B和TRHDE基因影响乌珠穆沁羊的生长性状，且这两个基因的组合效应也发挥了显著作用。这些SNP可能作为生长性状的遗传标记具有潜在价值，未来可用于乌珠穆沁羊的育种。需要进一步研究来证实我们的发现。
