CSTB and Dravet syndrome: Dp10Yey mice were generated to carry an internal duplication spanning the 39 Hsa21 protein-coding orthologs mapping to Mmu10, and several of these genes—such as ADAR2, S100B, CSTB, PRMT2, and TRPM2—have been shown to play a role in brain development and function, such that aberrant gene dosage may be related to intellectual disability in DS (Block et al., 2015, Gupta et al., 2016).