基于线粒体Cytb基因分析我国乌骨鸡遗传多样性

Genetic diversity of Chinese black bone chicken (Gallus gallus domesticus) assessed with the mitochondrial DNA Cytb gene

乌骨鸡(Gallus gallus domesticus)是我国优良的鸡遗传资源,通常被认为具有一定药用价值。为研究我国乌骨鸡品种的遗传多样性,对丝羽乌骨鸡、东乡绿壳蛋鸡、金湖乌凤鸡、余干乌骨鸡和竹丝鸡等5个乌骨鸡品种的197个个体线粒体DNA的Cytb基因全序列进行检测。结果表明:5个乌骨鸡品种的Cytb基因序列全长为1 143 bp,共检测到15个核苷酸多态位点,界定出9个单倍型。总体单倍型多样性、核苷酸多样性和平均核苷酸差异分别为0.715±0.018、0.001 23±0.000 54和1.404。中介网络图分析显示,5个乌骨鸡品种单倍型呈星状发散分布,不同群体包含的单倍型存在一定的差异,形态学和地理分布不明显。遗传距离分析表明,竹丝鸡和丝羽乌骨鸡遗传距离较远,母系可能来自其他品种。这一研究为我国乌骨鸡遗传资源的保护、选育和鉴定提供了遗传背景信息。

Black bone chickens(Gallus gallus domesticus) are excellent indigenous chicken resources in China and commonly believed to have medicinal properties. The study on the genetic diversity of the black bone chickens is of great significance for genetic conservation. For this study, the complete mitochondrial DNA Cytb sequences of 197 chickens from five breeds(Silkie, Dongxiang Blue-eggshell, Jinhu Black-bone, Yugan Black-bone and Zhusi) were analyzed. The size of full-length chicken Cytb gene of five black-bone breeds were 1 143 bp. A total of 15 variable sites that defined 9 haplotypes were identified. The average haplotype diversity, nucleotide diversity and mean number of nucleotide differences were 0.715±0.018, 0.001 23±0.000 54 and 1.404, respectively. The median network exhibited a star like phylogeny, haplotypes were dispersed in different breeds, and the distribution of morphology and geographical pattern was not obvious. This study suggested that genetic distance between Zhusi and Silkie was long, which verified that Zhusi chickens were hybridized from the other chicken breed as maternal line. The results can be used as a reference for preservation, improvement and identification of Chinese black bone chickens.