SYNGAP1 and early-onset autosomal dominant Alzheimer disease: Human orthologs of many of the downregulated genes, such as Kcnc1, Kcnb1, Kcnq2, Flna, Nos1, Pidd1, Syngap1, and Abca7 for example, are associated with epilepsy, intellectual disability, psychiatric disorder, and/or Alzheimer’s disease (41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51).