中文摘要：

【目的】建立一种通过内在的四肢骨关节评分来评估猪肢蹄结实度的方法，并计算关节评分与表观评估的肢蹄结实度之间的相关系数。此外，在F2、莱芜、二花脸、苏太和杜长大5个猪群中，研究三个位置功能候选基因HMGAl、C60rf106和ENSSSCG00000023160与猪肢蹄结实度之间的关联性。【方法】根据关节面裂痕的大小和深浅以及损伤的严重程度，对5块四肢骨的关节进行评分（1-5分）。如果关节面裂痕很大且很深，或损伤很严重，则评为1分；如果关节面没有裂痕和损伤，则评为5分。评分越高，说明关节越健康，肢蹄越结实。此外，基于笔者前期全基因组关联分析的结果，在猪7号染色体最强关联SNP两侧翼各0．2Mb的区域内，筛选出HMGAI、C60rfl06和ENSSSC600000023160三个位置功能候选基因。在F2群体中，通过基因测序，搜寻这3个基因的多态位点，并根据多态位点在6个物种间的保守性，筛选出11个多态位点。利用Taqman探针，对3个HMCAI位点和3个C60rfl06位点进行基因分型，而另一个基因的5个多态位点则通过基因型填补（genotypeimputation）方法进行基因分型。最后，利用R软件GenABEL程序包，分析最小等位基因频率（MAF）大于0．05的多态位点与肢蹄结实度之间的关联性。【结果】在C60rf106和ENSSSCG00000023160基因中，分别鉴别到174和5个多态位点。关节评分之间呈显著的正相关，绝大部关节评分与蹄趾、肢蹄和步态评分之间无相关，而与肱二头肌长度和重量呈显著的负相关。公猪的肩胛骨关节评分极显著低于母猪的评分，但是臂骨肩关节和后肢跗关节评分显著高于母猪相应的关节评分。在F2群体中，3个候选基因均与肢蹄结实度关联，但是ENSSSCG00000023160的关联程度不如另外2个基因强，可以排除它为肢蹄结实度的因果基因。因此，该基因没有在其余的4个群体中进行检?

英文摘要：

[Objective] The objective of this study is to develop a method to access the leg soundness through scoring the joint of limb bone and calculate the simple correlation coefficients among the scores for leg soundness in pigs. Furthermore, the association between three positional and functional candidate genes, namely HMGA1, C6orf106 and ENSSSCGO000023160, and leg soundness was also studied in F2, Laiwu, Erhualian, Sutai and DLY populations. [Method] The joint of five limb bones were scored according to the size and depth of rip on the joint surface and the worn-out degree of the joint. If the rip on the joint surface is very big and deep or the joint is seriously worn out, the joint is scored 1. On the other hand, if there is no rip on the joint surface and the joint doesn＇t have any degree of worn-out, the joint is scored 5. Higher the joint score is, healthier the joint is and sounder the leg is. Based on the authors＇ previous genome-wide association studies, three genes HMGA1, C6orf106 and ENSSSCGO000023160 were screened as positional and functional candidate genes to leg soundness in a 0.4 Mb region centered on the top SNP on SSC7. To search the polymorphic loci of the three genes in the F2 population, their DNA sequences were determined by a short-gun DNA sequence method. A total of 11 polymorphic loci were picked out according to their conservations among 6 species. The genotypes of 3 loci for HMGA1 and 3 loci for C6orf106 were determined using the Taqman method, and the genotypes of the other 5 loci for the third gene were inferred by genotype imputation just in the F2 population. At last, the GenABEL package of R was used to perform the association analysis between the loci with MAF〉0.05 and the traits. [Result] A total of 174 and 5 polymorphic loci were identified correlated with each other and were in C6orf106 and ENSSSCGO0000023160 genes, respectively. Joint scores were positively negatively correlated with the length and weight of biceps brachii, but most of them had no correlation with toe, leg a