DNA条形码技术在青海海东地区小型兽类鉴定中的应用

为弥补传统形态分类方法的不足,探究应用DNA条形码技术进行分子生物学鉴定的可行性,本研究用DNA条形码技术检测了青海省海东地区3目6科14属18种110只小型兽类的COI基因部分序列。分析所测COI基因序列可知:种内遗传距离≤3%,种间遗传距离5-10%,属间遗传距离12-19%,种间遗传距离显著大于种内遗传距离。NJ树显示同种个体聚为有很高支持度的单一分支。有6个个体(4只黄胸鼠、2只小家鼠)在现场鉴定中被误定为其他种类。研究结果表明使用条形码技术能纠正形态学鉴定中的错误,也说明动物线粒体COI基因是一个有效的DNA条形码标准基因。

Application for identification of small mammals by DNA barcoding in Haidong area, Qinghai Province, China

Because of the shortcomings of morphological classification,we studied the feasibility of DNA barcoding in the identification of small mammals.Small mammals belonging to 3 orders,6 families and 14 genera were collected from the Haidong region in Qinghai Province.We analyzed COI gene sequences from 110 small mammal samples and the results showed that the average intraspecific genetic distance was small than 3%,average interspecific distance ranged from 5% to 10% and intergenus distance 12-19%.The average interspecific genetic distance was significantly greater than the intraspecific genetic distance.A Neighbor-Joining tree showed that samples of the same species formed monophyletic groups with high support value.The NJ tree implied that 6 individuals were misidentified in the field.Our results suggest that the DNA barcoding can increase identification accuracy relative to using morphology alone,and also that the mitochondrial COI gene is an efficacious candidate for DNA barcoding.