The description above indicates that variations are associated with different conditions depending on each PAK gene: PAK1 pathogenic variants are associated with developmental delay, ID, ASD and macrocephaly, PAK2 variants with ASD only and PAK3 variants with ID, often along with ASD, ADHD, epilepsy, and, in numerous cases, microcephaly. This evidence concerns the gene PAK3 and microcephaly.