Expression and genomic imprinting of DCN, PON2 and PEG3 genes in porcine placenta

Imprinted genes play vital roles in the placental development and fetal growth in eutherian mammals. DCN (decorin), PON2 (paraoxonase 2) and PEG3 (paternally expressed 3) genes have been identified as imprinted genes in the mouse. Here, we detected the imprinting status of three genes in the porcine placenta on DG90 (day 90 of gestation) and the expression differences in Yorkshire and Meishan placenta on DG26, DG55 and DG90. The results indicated that the DCN and PON2 genes were not imprinted genes, while the PEG3 gene showed paternal monoallelic expression in porcine placenta. The expression of the DCN gene increased from DG26 to DG90 in both Yorkshire and Meishan pig placenta. However, this gene expression was greater in Yorkshire than Meishan pig on DG55. The expression of the PON2 gene was greater in Meishan pig than that in Yorkshire on DG26 and DG90. The PEG3 gene expression was not affected by day of pregnancy or breed. Data from the present study contribute to function genomic of porcine placental development.