基于mtDNA cyt b基因变异的中国黄牛品种间遗传关系分析  

Genetic relationship analysis of Chinese cattle breeds based on variation of mtDNA cyt b gene

作　　者：蔡欣[1,2] 雷初朝[1] 王珊[1] 薛恺[1] 胡沈容[1] 陈宏[1] 

机构地区：[1]西北农林科技大学动物科技学院,杨凌712100 [2]西南科技大学生命科学与工程学院,绵阳621010

出　　处：《四川大学学报（自然科学版）》2012年第5期1115-1120,共6页Journal of Sichuan University(Natural Science Edition)

基　　金：国家自然科学基金(30972080);国家支撑计划(2008ADB2B03-19);国家现代肉牛产业技术体系专项项目(Nycytx-38)

摘　　要：18个品种136个个体的mtDNA c yt b基因全序列不存在长度差异(1140 bp),均以ATG为起始密码子,中间无插入、缺失或终止密码子,以终止密码子AGA结束;一共检测到了105个替代突变位点,约占核苷酸总数(1140 bp)的9.2%.核苷酸多样性(Pi)为0.00923,一共定义了47个cyt b基因单倍型,单倍型多样性为0.848.105个突变位点中有65个转换和39个颠换,参考序列V00654的15615位点为中国黄牛cyt b基因变异的转换与颠换共存位点.北方黄牛(0.00550±0.00088)和南方品种(0.00655±0.00128)的平均遗传距离相对较小,但是两者之间的平均遗传距离(0.01271±0.00262)差异较大;中原牛种群和北方种群之间的遗传分化程度(0.01002±0.00193)要大于和南方种群之间的遗传分化程度(0.00891±0.00178),所以中原牛种群受南方瘤牛的遗传影响较大.中原牛种群内的晋南牛和秦川牛受北方普通的影响相对瘤牛要大;而鲁西牛、郏县红牛和南阳牛受南方瘤牛的影响较大.136 sequences of the cyt b gene in full length for 18 cattle breeds spanned 1140 bp, started with an ATG codon and ended with an AGA codon. No insertion/deletion or length variation was observed in these sequences. These sequences showed 105 polymorphic sites, representing 9.2% of the total DNA sequence analysed （1140 bp）, and belonged to 47 haplotypes defined by polymorphisms at 105 polymorphic sites. The overall nucleotide diversity and haplotype diversity of the cyt b genes in Chinese cattle samples analyzed were 0.00923 and 0. 848, respectively, which were higher than the reports from other studies. Among the 105 polymorphic sites, 65 were transitions and 39 were transversions. Transition and transversion coexisted in the cyt b genes in Chinese cattle at the site 15615 scored by the reference sequence of mtDNA genome （Accession no. V00654）. Chinese cattle breeds from the northern group （mean distance ± SD, 0. 00550±0. 00088） or from the southern group （0.00655±0. 00128） were more closely related in maternal lineage than those in the central group （0.00955±0.00190）. However, a higher genetic divergence existed between the northern and southern breeds （0.01271±0. 00262）. The genetic distance between the central group and the southern group （0. 00891 ±0. 00178） was shorter than between the central group and the northern group （0. 01002±0. 00193）, which indicates a greater genetic influence of the southern zebu to the central group of breeds. The genetic influence of Bostaurus to Qinchuan and Jinnan cattle was greater than that to the other breeds of the central area, whereas, Bos indicus contributed more to Jiaxian Red, Luxi and Nanyang cattle.

关 键 词：中国黄牛 MTDNA CYT B基因 变异特征 亲缘关系 

分 类 号：Q38[生物学—遗传学]