绵羊3号染色体的遗传连锁图谱构建及QTL定位

以四川凉山半细毛羊资源群体为研究对象, 选取位于绵羊3号染色体上的9个微卫星标记, 构建遗传连锁图谱, 用QTLExpress软件对影响绵羊生长发育的5个性状进行QTL定位分析。结果显示: (1) 9个微卫星标记的平均多态信息含量和平均群体杂合度分别为0.606 (0.378～0.738)、0.650 (0.404～0.766); (2) 连锁图谱总长为339.8 cM, 标记平均间距为42.5 cM, 略长于国际主要绵羊作图组织构建的图谱; (3) QTLExpress分析表明, 检测到影响羔羊断奶重、断奶日增重和成年体重的3个QTL, 分别位于99 cM、219 cM、273 cM处, 影响断奶日增重和成年体重的QTL都达到显著水平, 而影响羔羊断奶重的QTL未达到显著水平。

Construction of genetic linkage map and QTL detection of chromo-some 3 in sheep

Based on the reference family of Sichuan liangshan semi-fine sheep,the genetic linkage map was constructed by Crimap 2.4 software,which was used to detect the QTLs for growth traits by QTLExpress with nine microsatellite markers located on chromosome 3 in sheep.The results indicated that:(1) the mean of the polymorphic information content was 0.606(0.378-0.738),and the mean heterozygosity was 0.650(0.404-0.766);(2) the length of the linkage map was 339.8 cM,which was longer than the length of map built by the international major drawing organization for sheep with the average distance of markers of 42.5 cM;(3) The QTLs for weaning weight,weaning daily gain,and 2.5 year weight were detected at 99 cM,219 cM,273 cM,respectively.The effect of QTLs on weaning daily gain trait and 2.5 year weight trait were significant,except for weaning weight trait.