Estimation of coancestry in Iberian pigs using molecular markers
Estimation of coancestry in Iberian pigs using molecular markers
复制标题
DOI：
10.1023/a:1019921131171
复制
发表时间：
2002-01-01
影响因子：
2.2
通讯作者：
Silió, L
中科院分区：
文献类型：
--
作者：
Toro, M;Barragán, C;Silió, L
遗传标记提供了一个有用的工具，以估计成对的共同祖先在一个已知的系谱的情况下，个人之间。在目前的工作中，62头猪从两个相关的伊比利亚品种，Guadyerbas和Torbiscal，属于一个保护计划，自1945年以来，完全已知的谱系，已基因型为49个微卫星。四个系数，总结分子之间的相似性，个人连同8个估计的共祖先已经计算出这些信息。他们的价值观进行了比较，从完整或部分系谱计算的系谱共祖先。使用分子信息获得的八个估计大大低估了使用系谱分析计算的共祖先。还计算了估计值与系谱值之间的相关性。当考虑62只动物之间的所有成对比较时，该相关性较高，不同估计值在0.78和0.93之间。而Guadyerbas和Torbiscal种群的相关系数则显著下降，分别为0.49-0.69和0.37-0.47。所有的相关性是类似的，当使用简单的分子相似性系数，如分子同源性或相似性指数。最后，进行了模拟，以进一步探索所获得的结果。它的结论是，在基础人群中的等位基因频率的信息缺乏可能解释这些估计在复杂的家系人群中的偏差。
Genetic markers provide a useful tool to estimate pairwise coancestry between individuals in the absence of a known pedigree. In the present work 62 pigs from two related strains of Iberian breed, Guadyerbas and Torbiscal, belonging to a conservation programme with completely known pedigrees since 1945, have been genotyped for 49 microsatellites. Four coefficients that summarise molecular resemblance between individuals together with eight estimators of coancestry have been calculated from this information. Their values were compared with the genealogical coancestry, calculated from the complete or partial pedigree. The eight estimations obtained using molecular information substantially underestimate the coancestry calculated using the genealogical analysis. The correlation between the estimates and the genealogical values was also calculated. This correlation was high, between 0.78 and 0.93 for different estimators, when all pairwise comparisons among the 62 animals were considered. However, the correlation decreases remarkably to 0.49-0.69 and 0.37-0.47 for the Guadyerbas and Torbiscal populations respectively, when they were analysed separately. All the correlations were similar to those obtained when using simple coefficients of molecular resemblance such as molecular coancestry or similarity indexes. Finally, simulations were carried out to further explore the results obtained. It is concluded that lack of information on the allele frequencies in the base population may explain the bias of these estimators in populations with complex pedigrees.