Ovilo C, Fernández A, Rodríguez M C, Nieto M, Silió L
Departamento de Mejora Genética Animal, INIA, Ctra Coruña Km 7.5, 28040 Madrid, Spain.
Meat Sci. 2006 May;73(1):42-7. doi: 10.1016/j.meatsci.2005.10.016. Epub 2005 Dec 15.
The melanocortin receptor 4 (MC4R) gene is implicated in the regulation of feeding behaviour and body weight in humans and mice. A missense mutation (Asp298Asn) located in a highly conserved region of this gene has clearly been associated with backfat depth, feed intake and growth rate in different porcine lines. In this work the complete coding region of the gene was sequenced in samples from six pigs of a commercial hybrid line and two polymorphisms were detected at positions 709 (C/T) and 1426 (G/A). The last one corresponds to the missense mutation, and has been genotyped in 333 animals with phenotypic records and 68 out of their 81 parents. An association study of these genotypes with several performance and quality traits was performed within the statistical animal model framework. The results confirmed the effect of the missense mutation on growth and fat deposition traits (live weight at 140d and backfat depth), and supported new effects on carcass composition (loin and shoulder weights) and traits related to fat and meat quality (profile of fatty acids; muscle Minolta L(), a() and H(o) colour parameters). A transmission-disequilibrium test provided no evidence of spurious association due to population stratification.
黑皮质素受体4（MC4R）基因与人类和小鼠的摄食行为及体重调节有关。该基因高度保守区域中的一个错义突变（Asp298Asn）已明确与不同猪品系的背膘厚度、采食量和生长速度相关。在本研究中，对一个商业杂交品系的6头猪的样本进行了该基因完整编码区的测序，在第709位（C/T）和第1426位（G/A）检测到两个多态性。后者对应错义突变，已对333头有表型记录的动物及其81个亲本中的68个进行了基因分型。在统计动物模型框架内，对这些基因型与多个生产性能和品质性状进行了关联研究。结果证实了错义突变对生长和脂肪沉积性状（140日龄活重和背膘厚度）的影响，并支持其对胴体组成（腰部和肩部重量）以及与脂肪和肉质相关性状（脂肪酸谱；肌肉的Minolta L()、a()和H(o)颜色参数）有新的影响。传递不平衡检验未发现因群体分层导致的虚假关联证据。
