Single-cell methylomes identify neuronal subtypes and regulatory elements in mammalian cortex

Methylation and the single neuronal cell The presence or absence of methylation on chromosomal DNA can drive or repress gene expression. Now, a comprehensive map of methylation variation in neuronal cell populations, including a between-species comparison, illustrates how epigenetic diversity plays important roles in neuronal development. Luo et al. examined how DNA methylation is both similar and different within neurons at the single-nucleus level in humans and mice. They identified 16 mouse and 21 human neuronal clusters, with greater complexity of excitatory neurons in deep brain layers than in superficial layers. Science , this issue p. 600