Pérez-Enciso M, Clop A, Noguera J L, Ovilo C, Coll A, Folch J M, Babot D, Estany J, Oliver M A, Díaz I, Sánchez A
Area de Producció Animal, Centre UdL-IRTA, Lleida, Spain.
J Anim Sci. 2000 Oct;78(10):2525-31. doi: 10.2527/2000.78102525x.
Three Iberian boars were bred to 31 Landrace sows to produce 79 F1 pigs. Six F1 boars were mated to 73 F1 sows. The F2 progeny from 33 full-sib families (250 individuals) were genotyped for seven microsatellites spanning the length of chromosome 4. Least squares procedures for interval mapping were used to detect quantitative trait loci (QTL). A permutation test was used to establish nominal significance levels associated with QTL effects, and resulting probability levels were corrected to a genomewide basis. Observed QTL effects were (genomewide significance, position of maximum significance in centimorgans): percentage of linoleic acid in subcutaneous adipose tissue (< 0.01, 81); backfat thickness (< 0.01, 83); backfat weight (< 0.01, 80); longissimus muscle area (0.02, 83); live weight (0.19, 88); and percentage of oleic acid in subcutaneous adipose tissue (0.25, 81). Gene action was primarily additive. The Iberian genotypes were fatter, slower growing, and had lower linoleic and higher oleic acid contents than Landrace genotypes. The interval from 80 to 83 cM contains the FAT1 and A-FABP loci that have been shown previously to affect fat deposition in pigs. This is the first report of a QTL affecting fatty acid composition of subcutaneous adipose tissue in pigs and provides a guide for the metabolic pathways affected by candidate genes described in this region of chromosome 4.
选用三头伊比利亚公猪与31头长白母猪配种，产出79头F1代猪。选取6头F1代公猪与73头F1代母猪交配。对来自33个全同胞家系（共250头个体）的F2代后代进行了7个微卫星基因分型，这些微卫星分布于4号染色体全长。采用区间定位的最小二乘法程序来检测数量性状基因座（QTL）。运用排列检验来确定与QTL效应相关的名义显著性水平，并将所得概率水平校正到全基因组范围。观察到的QTL效应为（全基因组显著性，最大显著性位置（厘摩））：皮下脂肪组织中亚油酸百分比（<0.01，81）；背膘厚度（<0.01，83）；背膘重量（<0.01，80）；最长肌面积（0.02，83）；活体重量（0.19，88）；皮下脂肪组织中油酸百分比（0.25，81）。基因作用主要为加性效应。伊比利亚基因型的猪比长白基因型的猪更肥，生长速度更慢，亚油酸含量更低，油酸含量更高。80至83厘摩的区间包含先前已证明会影响猪脂肪沉积的FAT1和A-FABP基因座。这是关于影响猪皮下脂肪组织脂肪酸组成的QTL的首次报道，并为4号染色体该区域所描述的候选基因影响的代谢途径提供了指导。
