CXCR4 and lissencephaly spectrum disorders: We also noticed upregulation of genes implicated in cortical neuronal migration, out of which some are listed in Fig. 8C. These are genes that, when mutated in mice, cause lissencephaly (Reln, Dcx, Vldlr, Dab1; reviewed by Olson and Walsh, 2002) or other abnormalities related to defective cortical neuronal migration during development; Cspg5 (Zhang et al., 2013), Cxcr4 (reviewed by Tiveron and Cremer, 2008); Pak1 (Pan et al., 2015) and Tbr1 (Hevner et al., 2001).