Genome-wide QTL mapping for three traits related to teat number in a White Duroc x Erhualian pig resource population
Genome-wide QTL mapping for three traits related to teat number in a White Duroc x Erhualian pig resource population
复制标题
白杜洛克×二花莲猪资源群体中与乳头数相关的三个性状的全基因组QTL定位
DOI：
10.1186/1471-2156-10-6
复制
发表时间：
2009-02-18
期刊：
影响因子：
2.9
通讯作者：
Huang, Lusheng
中科院分区：
文献类型：
--
作者：
Ding, Nengshui;Guo, Yuanmei;Huang, Lusheng
研究背景：乳头数是猪生产中重要的生育性状，反映母猪的母性能力。这也是一个离散的，往往渠道化的特点，双边对称性与双方之间的微小差异，提供了一个潜在的权力，以评估波动的不对称性和发展的不稳定性。其遗传控制的知识仍然有限。本研究利用覆盖猪全基因组的183个微卫星进行了全基因组扫描，对白色杜洛克×二花脸大规模资源群体中与乳头数相关的3个性状，即乳头总数（TTN）、左右乳头数（LTN）和左右乳头数（RTN）进行了QTL定位。构建了一张总长度为2350.3cM、平均标记间距为12.84cM的性平均连锁图谱。在猪第1、3、4、5、6、7、8、12号染色体等8条常染色体上检测到11个TTN的全基因组显著QTL。在SSC6、9、13、14和16上检测到6个与该性状相关的QTL。SSC 1、3、4、5、6、7、8和12上的8个染色体区域均与LTN显著相关。除SSC6和SSC8上的QTL外，其余区域均为RTN的显著QTL。3个性状的极显著QTL均位于SSC 7上。除SSC1和SSC7上的3个QTL外，其余QTL的二花脸等位基因均表现为正的加性效应，白色杜洛克猪的二花脸等位基因使乳头数增加。在SSC1、6、9、13和16位点上，TTN位点均表现出显著的显性效应，而TTN位点仅在SSC12位点上表现出显著的印迹效应。结论：本研究结果不仅证实了以往试验中的QTL定位区域，而且还发现了5个新的影响乳头总数的QTL。验证了负责LTN和RTN的QTL区域之间的微小差异。进一步的精细映射应集中在具有小置信区间的一致识别区域，例如SSC 1，SSC 7和SSC 12上的区域。
Background: Teat number is an important fertility trait for pig production, reflecting the mothering ability of sows. It is also a discrete and often canalized trait presenting bilateral symmetry with minor differences between the two sides, providing a potential power to evaluate fluctuating asymmetry and developmental instability. The knowledge of its genetic control is still limited. In this study, a genome-wide scan was performed with 183 microsatellites covering the pig genome to identify quantitative trait loci (QTL) for three traits related to teat number including the total teat number (TTN), the teat number at the left (LTN) and right (RTN) sides in a large scale White Duroc x Erhualian resource population.Results: A sex-average linkage map with a total length of 2350.3 cM and an average marker interval of 12.84 cM was constructed. Eleven genome-wide significant QTL for TTN were detected on 8 autosomes including pig chromosomes (SSC) 1, 3, 4, 5, 6, 7, 8 and 12. Six suggestive QTL for this trait were detected on SSC6, 9, 13, 14 and 16. Eight chromosomal regions each on SSC1, 3, 4, 5, 6, 7, 8 and 12 showed significant associations with LTN. These regions were also evidenced as significant QTL for RTN except for those on SSC6 and SSC8. The most significant QTL for the 3 traits were all located on SSC7. Erhualian alleles at most of the identified QTL had positive additive effects except for three QTL on SSC1 and SSC7, at which White Duroc alleles increased teat numbers. On SSC1, 6, 9, 13 and 16, significant dominance effects were observed on TTN, and predominant imprinting effect on TTN was only detected on SSC12.Conclusion: The results not only confirmed the QTL regions from previous experiments, but also identified five new QTL for the total teat number in swine. Minor differences between the QTL regions responsible for LTN and RTN were validated. Further fine mapping should be focused on consistently identified regions with small confidence intervals, such as those on SSC1, SSC7 and SSC12.