Tain et al. (2016), demonstrated that melatonin could decrease renal levels of ace2, agt, and agtra1 genes. Additionally, melatonin attenuated hypertension through suppression of the renin-angiotensin system (Ohashi et al., 2019b). Recently, it has been reported and reviewed by several researchers, that aberrant methylation patterns of ACE and AGTR-1 promoter regions might be one of the underlying epigenetic mechanisms behind hypertension (Pei et al., 2015). The gene discussed is REN; the disease is Hypertension.