Two Novel SNPs of <i>PPARγ</i> Significantly Affect Weaning Growth Traits of Nanyang Cattle

Peroxisome-proliferator-activated receptor gamma (<i>PPARγ</i>) is a key transcription factor that controls adipocyte differentiation and energy in mammals. Therefore, <i>PPARγ</i> is a potential factor influencing animal growth traits. This study primarily evaluates <i>PPARγ</i> as candidate gene for growth traits of cattle and identifies potential molecular marker for cattle breeding. Per previous studies, <i>PPARγ</i> mRNA was mainly expressed at extremely high levels in adipose tissues as shown by quantitative real-time polymerase chain reaction analysis. Three novel SNPs of the bovine <i>PPARγ</i> gene were identified in 514 individuals from six Chinese cattle breeds: SNP1 (AC_000179.1 g.57386668 C &gt; G) in intron 2 and SNP2 (AC_000179.1 g.57431964 C &gt; T) and SNP3 (AC_000179.1 g.57431994 T &gt; C) in exon 7. The present study also investigated genetic characteristics of these SNP loci in six populations. Association analysis showed that SNP1 and SNP3 loci significantly affect weaning growth traits, especially body weight of Nanyang cattle. These results revealed that SNP1 and SNP3 are potential molecular markers for cattle breeding.过氧化物酶体增殖物激活受体γ（Peroxisome-proliferator-activated receptor gamma，PPARγ）是调控哺乳动物脂肪细胞分化与能量代谢的关键转录因子。因此，PPARγ是影响动物生长性状的潜在候选因子。本研究主要评估PPARγ作为牛生长性状候选基因的潜力，并筛选可用于牛育种的潜在分子标记。既往研究通过实时荧光定量聚合酶链反应（quantitative real-time polymerase chain reaction，qRT-PCR）分析发现，PPARγ mRNA主要在脂肪组织中呈高水平表达。研究团队在来自6个中国黄牛品种的514个个体中，鉴定出牛PPARγ基因的3个全新单核苷酸多态性（single nucleotide polymorphism，SNP）位点：位于内含子2区域的SNP1（AC_000179.1 g.57386668 C > G），以及位于外显子7区域的SNP2（AC_000179.1 g.57431964 C > T）与SNP3（AC_000179.1 g.57431994 T > C）。本研究还分析了这3个SNP位点在6个群体中的遗传特征。关联分析结果显示，SNP1与SNP3位点可显著影响断奶生长性状，尤其对南阳牛的体重影响显著。上述结果表明，SNP1与SNP3可作为牛育种的潜在分子标记。