Mutations in RAB39B had alreadyin 2010 been identified in (other) families with X-linked intellectual disabilityassociated with autism, epilepsy, and macrocephaly: In one large kindred(designated MRX72) from Sardinia, Italy, eight male members displayed moderate tosevere intellectual disability and global delay of all psychomotor development,three of whom had seizures and one an autism spectrum disorder [67]. Here, RAB39B is linked to Intellectual disability.