PTEN and Macrocephaly: The 13 studies in group A reported on a total of 1263 participants (51% male) with confirmed PTEN mutations or a PTEN-related condition (although, as with research into many rare syndrome groups, it is not possible to ascertain whether there is overlap between samples in some of these papers) and 93 control participants (including those with ASD with or without macrocephaly but no PTEN mutation and typically developing controls).