务川黑牛mtDNA遗传变异及起源进化分析

目的:测定务川黑牛mtDNA D-loop区全序列,以了解其遗传背景。方法:采用PCR直接测序方法测定务川黑牛mtD-NA D-loop区全序列。结果:32个个体D-loop区的全序列中,四种碱基A、T、C和G含量分别为:33.1%、28.4%、25.0%和13.5%,A+T平均含量61.5%。经过序列比对,共检测到57个变异位点,占所测mtDNA序列总长的6.26%,其中转换54个,颠换3个;产生17种单倍型,其中6种是普通牛单倍型,11种是瘤牛单倍型;平均核苷酸差异为22.623,单倍型多样度0.901±0.039,核苷酸多样度0.0249±0.00147。结论:务川黑牛这一品种遗传多样性非常丰富,据此构建的NJ进化树显示务川黑牛含有普通牛和瘤牛的血统。

Genetic Variation of Mitochondrial D- loop and Evolution Analysis in Wuchuan Black Cattle

Objective:To understand the genetic background of Wuchuan Black Cattle and sequenced the genetic diversity of 32 nucleotides in the mitochondrial DNA D-loop.Method:used PCR directly sequenced method to analyze the mitochondrial DNA D-loop of Wuchuan Black Cattle.Result:the average frequencies of the base composition A,T,C and G were33.1%,28.4%,25.0% and 13.5% respectively.Sequence comparison indicated 57 variations and 17 haplotypes were detected,included 11 Bos indicus haplotypes and 6 Bos taurus haplotypes,the average number of nucleotide difference was 22.623,haplotype diversity and nucleotide diversity were 0.901±0.039 and 0.0249±0.00147 respectively.Conclusion:That indicated a rich genetic diversity in Wuchuan Black Cattle.The phylogenetic tree constructed by using the neighbor-joining method showed the potential origin of Wuchuan Black Cattle was from Bos indicus and Bos taurus.