Over-expression of Dnmt1 in 3T3-L1 adipocytes increases methylation and decreases expression of Adipoq, while its knockdown results in the reverse (Kim et al., 2015), suggesting that direct hypermethylation and heterochromatin formation by DNMT1 at the Adipoq gene promoter is involved in obesity pathogenesis. The gene discussed is DNMT1; the disease is obesity disorder.