Aberrant DNA methylation is suspected to play a role in many cancers, e.g., hepatocellular carcinoma, glioblastoma, breast cancer, squamous cell lung cancer, thyroid cancer, and leukemia, (Daskalos et al., 2009; Eden et al., 2003; Gaudet et al., 2003; Heller et al., 2016; Morgan et al., 2018; Pakneshan et al., 2004; Schmelz et al., 2005; Stirzaker et al., 1997; Wen et al., 2018; Yu et al., 2013), and DNMT mutations are also the cause of developmental diseases such as hereditary sensory and autonomic neuropathy type 1E (HSAN1E) (Baets et al., 2015; Klein et al., 2013). Here, DNMT1 is linked to hereditary sensory neuropathy-deafness-dementia syndrome.