中文摘要：

为研究中国特色品系荷包猪SLA-DRa基因（又称SLA—DRa—HB），本试验设计引物，RT-PCR扩增3个个体荷包猪SLA-DRa全基因编码区，并克隆至pMD18-T载体，转化大肠杆菌JMl09感受态细胞，经酶切鉴定后筛选阳性克隆测序，比较分析与其他SLA-DRa等位基因的差异，并绘制分子进化树。结果显示，RT—PCR成功扩增出目的基因条带，大小约800bp。经克隆测序后分析，SLA-DRa-HB基因全长为779bp，编码区为1—759，共编码252个氨基酸。序列对比分析结果显示，SLA—DRa-HB的特征性变异集中在135、159、202位点。而穿膜区和胞浆功能区（203-252）变异位点为206、248。分子进化树分析显示，SLA-DRa-HB自成一系，且与其他等位基因的进化关系较近。本研究成功克隆荷包猪SLA-DRa基因，为进一步研究其功能奠定基础。

英文摘要：

In order to study SLA-DRa gene （also named as SLA-DRa-HB） from one of special breed of domestic pig, Hebao, primers were designed to amplify the coding domain of SLA-DRa from three Hebao pigs. Then,the amplified fragments were cloned into pMD18-T vector followed by transforming them into Escherichia coli JM109. After cleaving by the restricted enzymes, the positive clones were selected to be sequenced. The differences between SLA-DRa-HB and other SLA-DRa alleles were analyzed by sequences comparing,and then the phylogenetic tree was con- structed. The results showed that the interest of the fragments was successfully amplified by RT- PCR and the molecular weight was about 800 bp. By cloning and sequencing,the whole length of SLA-DRa-HB was 779 bp and the open reading fragments （ORF） of SLA-DRa-HB located at sites of 1 to 759 coding for 252 amino acids. Results of sequences comparision and analysis showed that the characterized amino acids of SLA-DRa-HB mainly focused on sites of 135,159 and 202,while the mutational sites in trans-membrane and cytoplasm were 206 and 248. Analyzing from the phy- logenetic tree,it showed that SLA-DRa-HB was clustered into one branch and they were relatively closed to other SLA-DRa alleles. In this research, the SLA-DRa alleles were cloned successfully from Hebao pigs and it would lay a base for study the function of the SLA-DRa genes.