Animal Breeding and Genomics Group, Wageningen University, Wageningen, The Netherlands.
PLoS One. 2012;7(2):e31825. doi: 10.1371/journal.pone.0031825. Epub 2012 Feb 29.
Genomic imprinting is an important epigenetic phenomenon, which on the phenotypic level can be detected by the difference between the two heterozygote classes of a gene. Imprinted genes are important in both the development of the placenta and the embryo, and we hypothesized that imprinted genes might be involved in female fertility traits. We therefore performed an association study for imprinted genes related to female fertility traits in two commercial pig populations. For this purpose, 309 SNPs in fifteen evolutionary conserved imprinted regions were genotyped on 689 and 1050 pigs from the two pig populations. A single SNP association study was used to detect additive, dominant and imprinting effects related to four reproduction traits; total number of piglets born, the number of piglets born alive, the total weight of the piglets born and the total weight of the piglets born alive. Several SNPs showed significant (q-value < 0.10) additive and dominant effects and one SNP showed a significant imprinting effect. The SNP with a significant imprinting effect is closely linked to DIO3, a gene involved in thyroid metabolism. The imprinting effect of this SNP explained approximately 1.6% of the phenotypic variance, which corresponded to approximately 15.5% of the additive genetic variance. In the other population, the imprinting effect of this QTL was not significant (q-value > 0.10), but had a similar effect as in the first population. The results of this study indicate a possible association between the imprinted gene DIO3 and female fertility traits in pigs.
基因组印迹是一种重要的表观遗传现象，在表型水平上可以通过基因的两个杂合子类之间的差异来检测。印迹基因在胎盘和胚胎的发育中都很重要，我们假设印迹基因可能与雌性生育特征有关。因此，我们在两个商业猪群中对与雌性生育特征相关的印迹基因进行了关联研究。为此，在两个猪群的 689 头和 1050 头猪中，对 15 个进化保守印迹区域中的 309 个 SNP 进行了基因分型。采用单 SNP 关联研究检测与四个繁殖性状相关的加性、显性和印迹效应；总产仔数、产活仔数、总产仔重和产活仔重。几个 SNP 显示出显著的（q 值<0.10）加性和显性效应，一个 SNP 显示出显著的印迹效应。具有显著印迹效应的 SNP 与 DIO3 紧密连锁，DIO3 是一个参与甲状腺代谢的基因。该 SNP 的印迹效应解释了约 1.6%的表型方差，相当于约 15.5%的加性遗传方差。在另一个群体中，该 QTL 的印迹效应不显著（q 值>0.10），但与第一个群体的效应相似。这项研究的结果表明，印迹基因 DIO3 与猪的雌性生育特征之间可能存在关联。
