Department of Human Anatomy, School of Basic Medical Sciences, Liaoning Medical University, Jinzhou 121001, P.R. China.
Exp Anim. 2014;63(1):73-8. doi: 10.1538/expanim.63.73.
Melanocortin 4 receptor (MC4R), which is associated with inherited human obesity, is involoved in food intake and body weight of mammals. To study the relationships between MC4R gene polymorphism and body weight in Beagle dogs, we detected and compared the nucleotide sequence of the whole coding region and 3'- and 5'- flanking regions of the dog MC4R gene (1214 bp). In 120 Beagle dogs, two SNPs (A420C, C895T) were identified and their relation with body weight was analyzed with RFLP-PCR method. The results showed that the SNP at A420C was significantly associated with canine body weight trait when it changed amino acid 101 of the MC4R protein from asparagine to threonine, while canine body weight variations were significant in female dogs when MC4R nonsense mutation at C895T. It suggested that the two SNPs might affect the MC4R gene's function which was relative to body weight in Beagle dogs. Therefore, MC4R was a candidate gene for selecting different size dogs with the MC4R SNPs (A420C, C895T) being potentially valuable as a genetic marker.
黑素皮质素 4 受体（MC4R）与人类遗传性肥胖有关，参与哺乳动物的食物摄入和体重调节。为了研究比格犬 MC4R 基因多态性与体重的关系，我们检测并比较了犬 MC4R 基因（1214bp）的整个编码区和 3'及 5'侧翼区的核苷酸序列。在 120 只比格犬中，发现了两个 SNP（A420C、C895T），并采用 RFLP-PCR 方法分析了它们与体重的关系。结果表明，当 MC4R 蛋白第 101 位氨基酸由天冬酰胺变为苏氨酸时，A420C 处的 SNP 与犬体重性状显著相关，而当 C895T 处发生 MC4R 无义突变时，雌性犬的体重变化显著。这表明这两个 SNP 可能影响 MC4R 基因的功能，从而影响比格犬的体重。因此，MC4R 是一个候选基因，可用于选择不同体型的犬，MC4R 上的 SNP（A420C、C895T）可能是有价值的遗传标记。
