Misztal I, Steyn Y, Lourenco D A L
Department of Animal and Dairy Science, University of Georgia, 425 River Road, Athens 30602.
JDS Commun. 2022 Jan 10;3(2):156-159. doi: 10.3168/jdsc.2021-0177. eCollection 2022 Mar.
Several types of multibreed genomic evaluation are in use. These include evaluation of crossbreds based on purebred SNP effects, joint evaluation of all purebreds and crossbreds with a single additive effect, and treating each purebred and crossbred group as a separate trait. Additionally, putative quantitative trait nucleotides can be exploited to increase the accuracy of prediction. Existing studies indicate that the prediction of crossbreds based on purebred data has low accuracy, that a joint evaluation can potentially provide accurate evaluations for crossbreds but could lower accuracy for purebreds compared with single-breed evaluations, and that the use of putative quantitative trait nucleotides only marginally increases the accuracy. One hypothesis is that genomic selection is based on estimation of clusters of independent chromosome segments. Subsequently, predicting a particular group type would require a reference population of the same type, and crosses with same breed percentage but different type (F vs. F) would, at best, use separate reference populations. The genomic selection of multibreed population is still an active research topic.
目前正在使用几种类型的多品种基因组评估方法。这些方法包括基于纯种单核苷酸多态性（SNP）效应评估杂交种、对所有纯种和杂交种进行单一加性效应的联合评估，以及将每个纯种和杂交种群体视为一个单独的性状。此外，可以利用推定的数量性状核苷酸来提高预测的准确性。现有研究表明，基于纯种数据预测杂交种的准确性较低，联合评估可能为杂交种提供准确评估，但与单一品种评估相比，可能会降低纯种评估的准确性，并且使用推定的数量性状核苷酸只会略微提高准确性。一种假设是，基因组选择基于对独立染色体片段簇的估计。随后，预测特定群体类型将需要相同类型的参考群体，并且具有相同品种百分比但不同类型（F与F）的杂交种最多只能使用单独的参考群体。多品种群体的基因组选择仍然是一个活跃的研究课题。
