在白色杜洛克×二花脸F2资源家系中定位影响猪210日龄8个体尺性状的QTL

QTL Mapping for Eight Traits Related to Porcine Body Dimensions at 210 Days in a White Duroc × Erhualian F_2 Resource Population

【目的】通过测量猪体长、体高、管围、胸围、胸宽、胸深、腹围和腿臀围等8个体尺性状,应用全基因组扫描定位影响猪体尺性状的数量性状位点(QTL)。【方法】在210日龄,活体测量白色杜洛克×二花脸资源群体129头F2个体的上述8个体尺性状,利用分布于猪18条常染色体和X染色体上的183个微卫星标记,对这129头F2个体及其父母和祖代亲本进行基因型检测。应用基于最小二乘线性回归分析的复合区间作图法在QTL Express进行在线QTL定位分析,并通过1000次的Permutation来确定不同显著水平的临界值。【结果】在8条染色体上共检测到19个影响猪体尺性状的QTL,其中位于4和7号染色体上的5个QTL达到基因组1%显著水平,位于2和7号染色体上的2个QTL达基因组5%显著水平,但是没有检测到影响胸深的QTL。【结论】影响猪体尺性状的QTL位点大多数分布于不同染色体区域,QTL所解释的表型方差介于5.23%—41.58%。白色杜洛克和二花脸中均存在增加表型值的有利等位基因。

【Objective】 The whole genome scanning strategy was employed to locate the quantitative trait loci （QTL） for eight porcine body-dimension traits, including body length, body height, cannon circumference, chest circumference, chest width, chest depth, abdominal circumference and hunkers circumference. 【Method】 A total of 129 F2 animals from a White Duroc × Erhuanlian resource population were measured for the eight traits mentioned above at 210 days of age. All of the 129 F2 individuals and their parents and grandparents were genotyped for 183 informative microsatellite markers across 18 porcine autosomes and the X chromosome. Quantitative trait loci （QTL） for these traits were identified by using an composite interval mapping method based on least-squares regression, which was performed by online software of QTL Express. Meanwhile, the threshold values were determined by an experiment-wise permutation of 1 000 iterations. 【Result】 A total of 19 QTLs were detected for the seven traits on 8 chromosomes, including five 1% genome-wide QTLs on SSC4 and SSC7 and two 5% genome-wide QTLs on SSC2 and SSC7. None QTL was identified for chest width. 【Conclusion】 Most of QTLs located in different chromosomes, and the phenotypic variance explained by each QTL ranged from 5.23% to 41.58%. The favorable alleles of some QTLs originated from White Duroc, but the others were from Erhualian.