SNP标记用于新疆5个绵羊品种亲子鉴定准确性的研究

Accuracy of parentage identification for 5 sheep breeds in Xinjiang based on SNPs

探讨单核苷酸多态性(single nucleotide polymorphism,SNP)标记用于新疆不同绵羊品种间亲子鉴定的准确性。新研究参照国际绵羊基因组学协会(International Sheep Genomics Consortium,ISGC)推荐的88个常染色体SNP构成的标记组合,计算其累积排除概率(cumulative probability of exclusion,CPE)并由此估计鉴定所需标记数量,用似然法验证鉴定的准确性。在新疆5个绵羊品种中,该标记组合的CPE随最小等位基因频率(minor allele frequency,MAF)的增大而增大,且MAF≥0.3时,CPE增加显著。当CPE随SNP数量的增加达到99.9%时,需要约50~60个SNP;当SNP数量达到ISGC推荐的88个时,CPE超过99.98%。似然法鉴定验证绵羊群体亲子关系的结果与系谱记录完全一致,置信度超过99%。研究证实了ISGC推荐的SNP标记组合在新疆绵羊品种中亲子鉴定准确性较高,为基于SNP标记估计不同绵羊品种间亲子关系的研究提供了理论依据。

The purpose of the study is to explore the accuracy of parentage identification based on Single Nucleotide Polymorphisms(SNPs)from different sheep breeds in Xinjiang.The research references to 88 autosomal SNPs recommended by International Sheep Genomics Consortium(ISGC),calculate the cumulative probability of exclusion(CPE)and estimates the number of SNPs to identify,uses likelihood method to verify the accuracy of identification.The results show that with the increase of minor allele frequency(MAF),the CPE shows an increasing trend as well and increases significantly when MAF ≥ 0.3.Furthermore,It takes about 50-60 SNPs when the CPE increases to 99.9% with the increase of SNPs and the CPE exceeds 99.95% when the number of SNPs reaches to 88 recommended by ISGC.The parent-child relationship of sheep breeds is consistent with the pedigrees,and the confidence is more than 99%.the work confirms that the SNPs recommended by ISGC have a relatively higher accuracy of parentage identification in Xinjiang sheep and built a new theoretical clue for estimating paternity relationship between different sheep breeds based on SNPs.