Intramuscular fat (IMF) is an important meat‐quality trait of pigs, which influences pork’s shearing force, hydraulics, tenderness and juicy flavor. However, to achieve a higher percentage of lean meat, pigs with lower backfat thickness (BF) are intensively selected for, which may lead to a reduction in pork quality. Therefore, the objective of this study was to locate loci that affect IMF without changing BF. A single‐step GWAS was performed on 950 Duroc pigs genotyped by a 50K SNP chip in order to detect genomic variants relevant to IMF and BF. The significant SNPs detected were afterwards divided into a BF subset (seven SNPs), an IMF subset (11 SNPs) and a subset of both traits (12 SNPs), according to their P‐value and LD. After SNP and QTL annotation, our results indicated that SSC1: 167938652, 166363826, 164829874 and 167171587 might be associated with IMF without changing BF. In the subset of both traits, we found that the combined effect of ALGA0006602 (SSC1: 159538854) and 12784636 (SSC1: 160773437) might improve the IMF without changing BF. Our gene annotation result showed that TLE3, ITGA11, SMAD6, PAQR5 and [RNF152^A/G × MC4R^A/A] genes might affect IMF independently of BF. We believe that the SNPs and genes identified in this study will be valuable for the future molecular breeding of IMF in Duroc pigs.

中文翻译：

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使用单步全基因组关联识别与杜洛克猪背脂肪厚度无关的肌内脂肪相关基因

肌内脂肪（IMF）是猪的重要肉质特征，它会影响猪肉的剪切力，水力学，嫩度和多汁风味。但是，为了获得更高的瘦肉比例，强烈选择了具有较低后脂肪厚度（BF）的猪，这可能会导致猪肉质量下降。因此，本研究的目的是在不改变BF的情况下定位影响IMF的基因座。为了检测与50 IMP和BF相关的基因组变异，对由50K SNP芯片进行基因分型的950头杜洛克猪进行了单步GWAS。检测出的显著个SNPs之后分成BF子集（7个SNP），一个子集IMF（11个SNP）和两个性状（12个SNP）的子集，根据它们的P值和LD。在对SNP和QTL进行注释后，我们的结果表明SSC1：167938652、166363826、164829874和167171587可能与IMF相关联而不改变BF。在这两个性状的子集中，我们发现ALGA0006602（SSC1：159538854）和12784636（SSC1：160773437）的组合作用可能会改善IMF而不会改变BF。我们的基因注释结果表明，TLE3，ITGA11，SMAD6，PAQR5和[ RNF152 ^{A / G} ×MC4R ^{A / A} ]基因可能独立于BF影响IMF。我们相信，本研究中鉴定的SNP和基因对于杜洛克猪IMF的未来分子育种非常有价值。