DNA methylation, one of the most well-characterized epigenetic modifications in mammals, plays a critical role in a variety of cellular processes. These include development (Greenberg & Bourc'his, 2019; Li, Bestor, & Jaenisch, 1992; Okano, Bell, Haber, & Li, 1999), differentiation (Ehrlich & Lacey, 2013), maintaining genome stability (Dodge et al., 2005; Karpf & Matsui, 2005), X-chromosome inactivation (Mohandas, Sparkes, & Shapiro, 1981; Sharp et al., 2011), and genomic imprinting (Li, Beard,