Genomic DNA methylation is one of the most important epigenetic mechanisms. Existing data of indoor air formaldehyde effect on DNA methylation patterns is limited. S-adenosylmethionine, the sole methyl donor in this reaction, is generally connected to the tetrahydrofolate and the methionine-homocysteine cycle and one carbon metabolism. In mammalian systems, as a normal intermediary metabolite, endogenous formaldehyde remains in equilibrium in blood and tissues. There are two ways that endogenous FA can be involved in one carbon pool. One is the production of 5, 10-methlene-THF formed by FA and...
