Effect of selenium deficiency on DNA methylation in muscle tissue of chickens

The aim of this study was to investigate the effects of selenium(Se) deficiency on the DNA methylation in the muscle tissue of chickens.Two hundred 1-day-old chickens were randomly allocated to two groups.The low-Se group was fed a Se-deficient basal diet(containing 0.033 mg.kg-1Se).Control group was fed a medium-Se diet(containing 0.15 mg.kg-1).Breast muscle,flight muscle and Leg muscle was collected when the chickens were 15,25,35,45 and 55 days old.DNA methylation levels were detected by HPLC,while the expression levels of DNA-methyltransferase 1(DNMT1) DNA-methyltransferase 3A(DNMT3A) and DNA-methyltransferase 3B(DNMT3B) mRNA were deter-mined by real-time PCR.The total levels of DNA methylation were decreasing.Selenium deficiency group expression of DNMT1,DNMT3A mRNA increased compared with control group and then it expression decreased.The expression of DNMT3B in each group was lower than the control group with age increased.Selenium can down-regulate the levels of DNA methylation in chicken muscle tissue.