ACTG1 and Williams syndrome: MCPH1 is involved in primary autosomal recessive microcephaly (Venkatesh & Suresh, 2014), BAZ1B is involved in the William-Beuren syndrome that also presents neuropsychological deficits (Fusco et al., 2014; Xiao et al., 2009) and ACTG1 mutations are involved in the Baraitser-Winter syndrome, another developmental disorder associated to intellectual disability (Rivière et al., 2012).