Department of Animal Science and Center for Integrated Animal Genomics, Iowa State University, Ames, IA 50011, USA.
Anim Genet. 2009 Dec;40(6):967-70. doi: 10.1111/j.1365-2052.2009.01932.x. Epub 2009 Jun 5.
Pigs have undergone long-term selection in commercial conditions for improved rate and efficiency of lean gain. Interestingly, it has been observed in both experimental and field conditions that leg weakness has increased over time, concurrent with the selection for improved rate of lean gain, while fatter animals tend to have better leg action, and foot and leg (FL) structure. The exact molecular mechanisms or individual genes responsible for this apparent genetic correlation between fatness and leg weakness and other physical adaptability traits have been less well reported. Based on our recent studies involving candidate genes and leg weakness traits, the present investigation has identified 30 SNPs from 26 genes that were found to be associated with 10th rib backfat in a sow population consisting of 2066 animals. The specific alleles associated with increased backfat tended to be associated with better overall leg action, as shown for the genes including MTHFR, WNT2, APOE, BMP8, GNRHR and OXTR, while inconsistent associations with the single FL structure trait and backfat were observed for other genes. This study suggests that in some cases there may be a common genetic mechanism or linked genes regulating fatness and leg weakness. Such relationships are clearly complex, and the utilization of genetic markers associated with both traits should be treated cautiously.
猪在商业条件下经历了长期的选择，以提高瘦肉生长的速度和效率。有趣的是，在实验和现场条件下都观察到，随着瘦肉生长速度的选择，腿部无力的情况随着时间的推移而增加，而肥胖的动物往往具有更好的腿部动作和脚部及腿部（FL）结构。导致这种肥胖和腿部无力之间以及其他身体适应性特征之间明显遗传相关性的具体分子机制或个别基因，尚未得到充分报道。基于我们最近涉及候选基因和腿部无力特征的研究，本研究从 26 个基因中鉴定出 30 个 SNP，这些 SNP 与一个由 2066 头母猪组成的群体中的第 10 肋骨背膘厚相关。与背膘增加相关的特定等位基因往往与更好的整体腿部动作相关，如 MTHFR、WNT2、APOE、BMP8、GNRHR 和 OXTR 等基因所示，而其他基因与单一的 FL 结构特征和背膘之间的关联不一致。本研究表明，在某些情况下，可能存在调节肥胖和腿部无力的共同遗传机制或连锁基因。这种关系显然很复杂，与这两个特征相关的遗传标记的利用应该谨慎对待。
