应用微卫星DNA标记鉴别沼泽型水牛与河流型水牛的杂交个体

Genetic Identification of Swamp-River Buffalo Hybrids Based on Microsatellite DNA Markers

为了探索应用DNA标记鉴定沼泽型水牛与河流型水牛杂种后代的技术方法并分析中国水牛资源状况,以采自18个本地沼泽型水牛群体、2个引进河流型水牛品种及1个杂交水牛群体的共992份样本为试验材料,检测这些样本在30个微卫星座位上的基因型。结果显示,2种类型水牛间具有显著的遗传差异,30个标记的平均分化指数(FST)为(0.310±0.193)。利用个体多座位联合基因型数据,多变量对应分析(multivariate correspondence analysis)和基于模型的贝叶斯聚类(model-based Bayesian clustering)2种统计方法都能够灵敏地区分出纯种个体及杂种后代。此外,基于上述统计方法的群体遗传混合分析表明中国水牛总体上具有纯正的沼泽型水牛血统。本研究为今后开展中国沼泽型水牛的品种资源评价、制定保种决策提供了技术依据。

In order to develop a molecular method to detect swamp-river buffalo hybrids using genetic markers and characterize the status of Chinese buffalo recourses,thirty microsatellite markers were genotyped in 992 individuals that represented 18 indigenous swamp buffalo populations,2 exotic river buffalo breeds,and 1 crossbreeding population.Results reflected that there existed considerable genetic differentiation between two buffalo types with FST = 0.310±0.193.Based on microsatellite multi-locus genotypes,both the model-based Bayesian STRUCTURE analysis and the multivariate correspondence analysis could sensitively distinguish pure swamp or river buffalo and hybrid individuals.Moreover,results of genetic admixture analysis indicated that all Chinese local buffalo populations generally showed pure swamp ancestry.These findings may provide a technique basis for objectively assessing Chinese swamp buffalo genetic resources and making conservation decisions.