【摘要】 为了研究甘肃境内部分马群体的遗传多样性、遗传结构和母系起源，试验采用DNA测序技术对甘肃4个马群体(岔口驿马49匹、河曲马20匹、山丹马30匹和肃南马34匹)共133个个体血样的线粒体DNA(mitochondrial DNA, mtDNA)中的细胞色素b(cytochrome b, Cytb)基因进行PCR扩增，并对4个马群体的Cytb基因序列特征、遗传多样性、遗传距离、遗传分化与变异进行了分析，结合其他马群体的Cytb基因序列构建了系统发育树单位型网络关系图。结果表明：4个马群体Cytb基因序列全长1 140 bp, A+T含量(54.6%)大于G+C含量(45.4%),共检测到46个多态位点，33种单倍型；总单倍型多样度为0.933 2±0.010 0,总核苷酸多样度为0.003 85±0.000 17,总平均核苷酸差异为4.371 4,平均Tajima’s D值和Fu’s Fs值分别为-1.035 2和-13.057;4个马群体间的遗传距离、遗传变异系数和基因流的范围分别为0.003 5～0.004 2,0.019 23～0.091 32,4.975～25.504;4个马群体内的遗传变异(94.54%)远大于其群体间的遗传变异(5.46%);4个马群体的33种单倍型分散于6个支系(A～F)中。说明甘肃4个马群体间亲缘关系较近，都具有较高的遗传多样性且均为多母系起源。更多还原

【Abstract】 In order to study the genetic diversity, genetic structure and maternal origin of some equine populations in Gansu Province, cytochrome b(Cytb) gene of mitochondrial DNA(mtDNA) was amplified by PCR from 133 individuals from four populations of horses in Gansu Province(49 Chakouyi horses, 20 Hequ horses, 30 Shandan horses and 34 Sunan horses) by DNA sequencing. The sequence characteristics, genetic diversity, genetic distance, genetic differentiation and variation of Cytb gene in four equine populations were analyzed, and phylogenetic trees and haplotype network relationship diagram were constructed by combining the Cytb gene sequence of other horse populations. The results showed that the total length of Cytb gene sequence in four equine populations was 1 140 bp, and the A+T content(54.6%) was greater than G+C content(45.4%). A total of 46 polymorphic loci and 33 haplotypes were detected. The total haplotype diversity was 0.933 2±0.010 0; the total nucleotide diversity was 0.003 85±0.000 17, and the total mean nucleotide difference was 4.371 3. The average Tajima’s D value and Fu’s Fs value were-1.035 2 and-13.057, respectively. The ranges of genetic distance, genetic coefficient of variation and gene flow were 0.003 5-0.004 2, 0.019 23-0.091 32, 4.975-25.504, respectively. The genetic variation in the four herds(94.54%) was much higher than that among the populations(5.46%). The 33 haplotypes from four equine populations were dispersed in six clades(A-F). These results indicated that the four horse populations in Gansu Province were closely related, with high genetic diversity and multi-matrilineal origin.更多还原