海子水牛Cyt b基因序列分析

测定了18头海子水牛细胞色素b(Cyt b)基因全序列(1 140 bp)并对其进行了分析。Cyt b基因1 140个位点中,共发现10个可变位点,均为转换,其中1个位点引起氨基酸更换替代,其余可变位点均为同义替换。序列分析表明,海子水牛Cyt b基因表现出明显的碱基组成偏倚和密码子使用偏倚。研究发现,海子水牛终止密码子包括AGA和AGG两种,其中AGG为牛亚科动物Cyt b基因的终止密码子之一是国内外首次报道。18条Cyt b基因序列共定义了4种单倍型,单倍型多样性(Hd)为0.527,核苷酸多样性(Pi)为0.004 63,表明海子水牛的遗传多样度较高,推测海子水牛可能存在两种甚至更多不同的母系起源。

Sequence Analysis of Cyt b Gene of Haizi Buffalo

The cytochrome b(Cyt b) gene complete sequences(1 140 bp) of 18 Haizi buffalos were sequenced and analyzed.Among 1 140 sites of Cyt b gene,10 variable sites were found,all of which were transitions.In 10 variable sites,only one site caused amino-acid replacement substitution,and the other were all synonymous substitutions.Sequence analysis showed that there were remarkable base composition bias and codon usage bias.The results also showed that there were two stop codons(AGA and AGG) in Cyt b gene in Haizi buffalo,and it was first reported that AGG was one of the stop codons in Cyt b gene in Bovidae.18 Cyt b gene sequences defined 4 haplotypes,and the haplotype diversity(Hd) and Nucleotide diversity(Pi) were 0.527 and 0.004 63 respectively,showing abundant genetic diversity in Haizi buffalo.The data also suggested that there were two or more matriline origins in Haizi buffalo.