CAJ | 학술논문

以PCR为基础的分子标记以及其他检测技术的发展,使得大规模的标记分析成为现实.这也为通过大群体标记分析,然后基于基因型选择挑选合适的小群体,从而提高QTL定位准确性和精度提供了可能.以一个包含294个家系的重组自交系(RIL)群体为例,通过基因型选择和随机选择的办法产生了一系列大小不等的亚群体,比较了两类群体QTL定位的结果.分析表明:相同大小的基因型选择群体与随机群体相比性状的表型分布都符合正态分布;标记的偏分离情况也没有明显的差别,都随着群体大小的增大,偏分离的比例也逐渐增大.但同等大小的基因型选择群体比随机群体的交换富集率(CE)要大,且随着选择强度的增大不断增大,如群体大小为270时,CE=1.04,群体大小为30时,CE=1.45.总体上,随着群体大小的增加,不管是随机群体还是选择群体,其QTL检测能力、灵敏性和特异性也随之增加,但选择群体的检测能力、灵敏性和特异性总体上要好于随机群体.当群体大于或等于240时,其QTL检测能力基本没有差别;群体大小大于或等于210时,其QTL检测的灵敏性和特异性也没有什么差别.这也说明:选择强度越大,效果越明显.以QTL1-LOD区间作为衡量QTL精度的一个指标,结果显示所有基因型选择群体都比相同大小随机群体的QTL定位精度高.目前QTL定位研究中,基因型数据较表型数据而言更容易准确获得,因此通过基因型选择可以更好的优化群体结构,减少田间实验的工作量,提高全基因组水平QTL作图的精度,为随后的QTL辅助选择和精细定位以及克隆提供帮助.
이PCR위기출적분자표기이급기타검측기술적발전,사득대규모적표기분석성위현실.저야위통과대군체표기분석,연후기우기인형선택도선합괄적소군체,종이제고QTL정위준학성화정도제공료가능.이일개포함294개가계적중조자교계(RIL)군체위례,통과기인형선택화수궤선택적판법산생료일계렬대소불등적아군체,비교료량류군체QTL정위적결과.분석표명:상동대소적기인형선택군체여수궤군체상비성상적표형분포도부합정태분포;표기적편분리정황야몰유명현적차별,도수착군체대소적증대,편분리적비례야축점증대.단동등대소적기인형선택군체비수궤군체적교환부집솔(CE)요대,차수착선택강도적증대불단증대,여군체대소위270시,CE=1.04,군체대소위30시,CE=1.45.총체상,수착군체대소적증가,불관시수궤군체환시선택군체,기QTL검측능력、령민성화특이성야수지증가,단선택군체적검측능력、령민성화특이성총체상요호우수궤군체.당군체대우혹등우240시,기QTL검측능력기본몰유차별;군체대소대우혹등우210시,기QTL검측적령민성화특이성야몰유십요차별.저야설명:선택강도월대,효과월명현.이QTL1-LOD구간작위형량QTL정도적일개지표,결과현시소유기인형선택군체도비상동대소수궤군체적QTL정위정도고.목전QTL정위연구중,기인형수거교표형수거이언경용역준학획득,인차통과기인형선택가이경호적우화군체결구,감소전간실험적공작량,제고전기인조수평QTL작도적정도,위수후적QTL보조선택화정세정위이급극륭제공방조.
The QTL mapping results were compared with the genotypically selected and random samples of the same size on the base of a RIL population. The results demonstrated that there were no obvious differences in the trait distribution and marker segregation distortion between the genotypically selected and random samples with the same population size. However, a significant increase in QTL detection power, sensitivity, specificity, and QTL resolution in the genotypically selected samples were observed. Moreover, the highly significant effect was detected in small size of genotypically selected samples. In QTL mapping,phenotyping is a more sensitive limiting factor than genotyping so that the selection of samples could be an attractive strategy for increasing genome-wide QTL mapping resolution. The efficient selection of samples should be more helpful for QTL maker assistant selection, fine mapping, and QTL cloning.