基因型选择和基因辅助BLUP对不同遗传力性状的选择效果

Effects of Genotype Selection and Gene-assisted BLUP for Selection on the Traits with Different Heritabilities

为揭示性状遗传力对基因型选择(GTS)和基因辅助BLUP(GBLUP)选择效果的影响,探讨基因辅助选择相对于常规动物模型BLUP选择方法的效率,在假定目标性状同时受1个QTL和多基因共同控制的前提下,采用随机模拟方法,研究了在一个闭锁群体内分别采用常规动物模型BLUP、GTS和GBLUP方法对不同遗传力性状实施连续选择时的效果。结果表明:在一定世代内,性状遗传力越高,3种选择方法所获得的遗传进展越大;GBLUP方法可以对QTL和多基因效应实施有效选择,可望获得优于常规BLUP方法的选择效果;GTS只考虑了QTL基因型而无法兼顾多基因效应,其选择进展反而不如常规BLUP选择。基因辅助选择的优势在于可对QTL进行更为准确的选择。当遗传力较低、选择世代数较短时,其对QTL选择的效率较高。在长期选择下,不断检测并确认"新"的QTL,是保持其持续选择优势的关键。

In order to investigate the effects of trait heritability on the two gene-assisted selection （GAS） methods,genotype selection （GTS） and gene-assisted best linear unbiased prediction （GBLUP）,and to reveal the relative efficiency of GAS on conventional animal model best linear unbiased prediction （BLUP） selection,assumed that the target trait was controlled by one quantitative trait locus （QTL） and polygenes,the stochastic simulation method was used to compare the effects of continuous selection on the traits with different heritabilities by BLUP,GTS and GBLUP.The results showed that the higher the trait heritability was,the larger genetic responses would be gained from the three methods ; GBLUP could select the effects of QTL and polygenes effectively,which would gain higher genetic progress than that of conventional BLUP; although it could increase the QTL response,the total genetic response of GTS was lower than that of conventional BLUP,because it did not consider the polygenic effects.The superiority of GAS on conventional selection was that it had a higher accuracy of selection on QTL and a higher efficiency when selected those traits with lower heritability in short-term selection.It was the key that the ‘new＇ QTL should be identified and confirmed for maintaining the sustainable superiority of GAS in long-term selection.