Although one might expect an increase in DNMT3a or DNMT3b to be primarily involved in initiating pro-fibrotic DNA methylation patterns, studies in the liver, lung, heart, kidneys and systemic sclerosis have implicated a role for elevated DNMT1 and/or DNMT3 or DNMT3b in fibrosis [28, 47, 57, 71, 73–75]. Here, DNMT1 is linked to systemic sclerosis.