Rohrer G A, Keele J W
U.S. Meat Animal Research Center, USDA, ARS, Clay Center, NE 68933, USA.
J Anim Sci. 1998 Sep;76(9):2255-62. doi: 10.2527/1998.7692255x.
A genomic scan was conducted on 540 reciprocal backcross Meishan x White composite pigs for hot carcass weight (HCWT); loin eye area (LOIN); carcass length (CRCL); belly weight (BELLY); and weight of trimmed ham, loin, picnic, and Boston butt adjusted to a constant live (TWPLWT) or carcass (TWPCWT) weight. Genetic markers spanned the entire porcine linkage map and were spaced at approximately 20-cM intervals. Grandparental breed of origin for all chromosomal segments was determined using multipoint linkage procedures, and a least squares regression analysis was conducted. Nominal P-values were converted to a genome-wide level of significance to adjust for the number of tests actually conducted. Seven associations were significant at the genome-wide level relating to chromosomes 1 (SSC 1), 7 (SSC 7), and X (SSC X). The SSC 1 region affected LOIN, TWPLWT, and TWPCWT; SSC 7 affected HWCT and CRCL; and SSC X affected TWPLWT and TWPCWT. Twelve associations relating to seven chromosomal regions (including SSC 1 and X) presented suggestive evidence for quantitative trait loci (QTL), and many of these regions are likely to contain QTL. Chromosomes 8 and 14 had two and three traits with suggestive evidence for QTL, respectively. Many pleiotropic effects were detected for regions on SSC 1, 7, 14, and X in this study and a companion study looking for fat deposition QTL in the same population. In addition, SSC 4 was nearly significant for CRCL in the same region identified as affecting backfat in a wild boar x Large White population. These results expand our knowledge of the inheritance of quantitative traits and are directly relevant to composite populations containing Meishan germplasm.
对540头梅山猪与白色复合猪的正反交回交猪进行了基因组扫描，测定了热胴体重（HCWT）、眼肌面积（LOIN）、胴体长度（CRCL）、腹部重量（BELLY）以及调整至恒定活重（TWPLWT）或胴体重（TWPCWT）的修整后火腿、腰肉、野餐肉和波士顿肩肉的重量。遗传标记覆盖了整个猪的连锁图谱，间隔约为20厘摩。使用多点连锁程序确定所有染色体片段的祖代品种，并进行最小二乘回归分析。将名义P值转换为全基因组显著性水平，以校正实际进行的测试数量。在全基因组水平上，有7个关联与1号染色体（SSC 1）、7号染色体（SSC 7）和X染色体（SSC X）显著相关。SSC 1区域影响LOIN、TWPLWT和TWPCWT；SSC 7影响HWCT和CRCL；SSC X影响TWPLWT和TWPCWT。与7个染色体区域（包括SSC 1和X）相关的12个关联为数量性状位点（QTL）提供了暗示性证据，其中许多区域可能包含QTL。8号和14号染色体分别有2个和3个性状有QTL的暗示性证据。在本研究以及一项在同一群体中寻找脂肪沉积QTL的配套研究中，检测到SSC 1、7、14和X染色体区域存在许多多效性效应。此外，在野猪与大白猪群体中被确定影响背膘的同一区域，SSC 4对CRCL的影响接近显著水平。这些结果扩展了我们对数量性状遗传的认识，并且与含有梅山种质的复合群体直接相关。
