Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Genètica i Millora Animal, 25198 Lleida, Spain.
J Anim Sci. 2011 Oct;89(10):2963-71. doi: 10.2527/jas.2011-3974. Epub 2011 May 13.
Intramuscular fat (IMF) storage is a biological process with a strong impact on nutritional and technological properties of meat and also with relevant consequences on human health. The genetic architecture of IMF content and composition phenotypes has been thoroughly studied in pigs through the identification of QTL and the estimation of genetic parameters. A question that has not been elucidated yet is if the genetic determinants of IMF-related phenotypes are muscle specific or, conversely, have broad effects on the whole skeletal muscle compartment. We have addressed this question by generating lipid QTL maps for 2 muscles with a high commercial value, gluteus medius (GM) and longissimus thoracis et lumborum (LTL), in a Duroc commercial population (n = 350). Our data support a lack of concordance between the GM and LTL QTL maps, suggesting that the effects of polymorphisms influencing IMF, cholesterol, and fatty acid contents are modulated to some extent by complex spatial factors related to muscle location, metabolism, and function. These results have important implications on the implementation of genomic selection schemes aimed to improve the lipid profile of swine meat.
肌内脂肪（IMF）储存是一个对肉的营养和技术特性有强烈影响的生物学过程，也对人类健康有相关影响。通过鉴定 QTL 和估计遗传参数，已经在猪中对 IMF 含量和组成表型的遗传结构进行了深入研究。一个尚未阐明的问题是，IMF 相关表型的遗传决定因素是肌肉特异性的，还是相反，对整个骨骼肌室有广泛影响。我们通过在杜洛克商业群体（n = 350）中生成具有高商业价值的臀中肌（GM）和腰大肌（LTL）的脂质 QTL 图谱来解决这个问题。我们的数据支持 GM 和 LTL QTL 图谱之间缺乏一致性的观点，表明影响 IMF、胆固醇和脂肪酸含量的多态性的影响在一定程度上受到与肌肉位置、代谢和功能相关的复杂空间因素的调节。这些结果对实施旨在改善猪肉脂质谱的基因组选择计划具有重要意义。
