PIK3CA and megalencephaly: Recently, germline and somatic point mutations in AKT3, PIK3R2, and PIK3CA have been detected in the megalencephaly-related syndrome, and somatic gain of function point mutations in AKT3, PIK3CA, and MTOR has also been detected in HME, the most severe type of megalencephaly (Baek et al. 2015; Jansen et al. 2015; Lee et al. 2012; Nakamura et al. 2014; Poduri et al. 2012; Riviere et al. 2012).