中文摘要：

二脂酰甘油酰基转移酶（diacylglycerol acyltransferase，DGAn是催化真核生物甘油三酯合成最后一步反应的关键酶和限速酶，包括DGATl和DGAT2两种。DGAT2对调节脂肪代谢、脂类在组织中的沉积及生长发育发挥重要作用。为研究鸡（Callus gallus）DGAT2基因遗传多态性及其与生产性能的相关性，本研究以固始鸡×安卡鸡杂交F：资源群体（n=860）为研究材料，利用聚合酶链式反应限制性片段长度多态性（polymerase chain reaction．restriction fragment length polymorphism，PCR—RFLP）技术检测DGAT2基因的多态性，并分析多态性与生长性状、肉质性状、屠体性状、血液生化指标和肌纤维性状之间的关联性。结果显示，DGAT2基因第7外显子g．13955位置存在一个同义突变位点（C→T），PCR扩增产物被限制性酶TaqI酶切消化后显示出CC、CT和TT三种不同基因型，基因型频率分别为0．49、0．48和0．03，等位基因A和B的频率分别为0．73和0．27。相关性分析显示，固始鸡×安卡鸡F2代个体初生重，2、4周龄体重、4、8周龄体尺指标及肌内脂肪含量在不同基因型之间差异显著（P〈0．05），CC基因型多数性状值显著高于TT基因型，对其他指标在统计学上无显著影响（P〉0．05）。由以上结果可以推测，鸡DGAT2基因g．13955C〉T与生长发育有关，且C等位基因为优势基因，有望成为家禽品种选育的潜在DNA分子标记。

英文摘要：

The final and critical step in the synthesis of triglycerides is catalyzed by diacylglycerol acyltransferase 1 （DGAT1） and DGAT2 enzymes. DGAT2 gene plays an important role in fat metabolism, lipid deposition in the organization and growing development. In order to invest the association of polymorphism of DGAT2 with production performance in chicken （Gallus gallus）, the genetic polymorphism of DGAT2 gene was investigated by polymerase chain reaction-restriction fragment length polymorphism （PCR-RELP）, and the association of polymorphisms with production performance, which included the growth traits, meat quality traits, carcass traits, blood biochemical indices and muscle fiber traits, was analyzed. The results indicated that one synonymous mutation site （C→T） was detected in exon 7 of DGAT2 gene. Three genotypes （CC, CT and TT） were found at g.13955C〉T mutation locus by digesting the PCR product with Taq I, and the frequency of CC, CT and TT genotypes was 0.49, 0.48 and 0.03, respectively. The results showed that the polymorphisms of the g.13955C〉T site of DGAT2 gene had significant association （P〈0.05） with birth weight, 2 and 4 week body weight, 4 and 8 week index of body measurements and intramuscular fat in different genotype, and most CC genotype character value significantly greater than those of TT genotype, while had no significant association with other traits （P〉0.05）. The result demonstrated that g.13955C〉T site of chicken DGAT2 gene related to the growth and development, and C allele was dominant genes, it can be candidate molecular markers for the poultry breeding.