广灵驴分子系谱的建立及群体遗传结构分析

Construction of Molecular Pedigree and Analysis of Population Genetic Structure of Guangling Donkey

旨在对广灵县优种驴场保种群体进行调查的基础上构建分子系谱,并对其种群的遗传结构进行分析。本研究采集保种群成年、体况良好的广灵驴(体重350~400 kg)颈静脉血10 mL(n=107),其中公驴13份,母驴94份,抗凝处理后提取全血DNA。采用12个微卫星标记进行荧光PCR扩增后,用ABI3730测序仪进行分型。分型结果采用Cervus 2.0和Pedigraph 2.4软件构建分子系谱,同时采用STRUCTURE2.3和Fstat软件计算群体遗传参数,采用R语言的hclust函数绘制7头公驴及其后代的系统发生NJ树(邻接树)。结果,对107头种驴进行了分子系谱构建,找到了30头子代的父亲和7头子代的母亲,系谱可靠性>90%;微卫星标记的平均观测杂合度(H_(Obs))和多态信息含量(PIC)分别为0.6765和0.5939,标记遗传多样性较高;NJ树对7个公驴家系进行了聚类;群体分化系数(F_(ST))为0.184,群体平均近交系数(F_(IT))为0.033,群体内近交系数(F_(IS))为-0.238,且群体处于哈代-温伯格平衡状态,存在很弱的近交。本研究建立了广灵驴保种群可靠性较高的分子系谱并对其遗传结构进行了分析,证明该群体遗传多态性较高,群体近交系数较低,处于较好的保种状态,具有较大的品种资源开发潜力。

This study aimed to construct the molecular pedigree based on investigating of Guangling donkey population in breeding farm,and analyze its genetic structure.A total of 107(including 13 males and 94 females)jugular vein blood of healthy adult donkey(body weight:350-400 kg)were collected,after condensant treatment,the DNA was extracted.After using 12 SSR markers for fluorescence PCR amplification,the products were genotyped on ABI3730 sequencing instrument.The molecular pedigree was constructed by Cervus 2.0 and Pedigraph 2.4 softwares,and the population genetic parameters were calculated by STRUCTURE2.3 and Fstat softwares.Moreover,the phylogenetic tree(NJ tree)of 7 male donkey and their offspring was established by hclust function of R software.In all,107 donkey were included in the molecular pedigree and only 30 offspring were matched with their fathers,and 7 offspring were matched with their mothers,the reliance level of pedigree was higher than 90%.The H_(Ob) and PIC of SSR markers were 0.6765 and 0.5939,respectively.NJ phylogenetic tree included 7 male families,the F_(ST) of the current population was 0.184,the F_(IT) was 0.033,and F_(IS) was-0.238,the population was in Hardy-Weinberg equilibrium.This study constructed a high reliable molecular pedigree of Guangling donkey and analyzed its genetic structure.The results show that the Guangling donkey population has high genetic polymorphisms,with low inbreeding coefficient.Therefore,it is worthful to preserve the genetic information and develop its breed potentials.