Although her son was born from uncontrolled pregnancy with high blood levels of phenylalanine and poorly adhered to low-phenylalanine diet himself, he also escaped the intellectual disability (IQ 80–85) indicating a possible joint modifying role of p.Pro1591Ala in SHANK1 and p.Pro1716Thr in SHANK3. This evidence concerns the gene SHANK1 and Intellectual disability.