Phelan–McDermid syndrome (PMS), also known as 22q13.3 deletion syndrome (OMIM #606232), is a rare neurodevelopmental disorder that can be caused by a terminal deletion or other rearrangement affecting the distal region of chromosome 22q, or pathogenic variants within the SHANK3 gene [1,2]. Here, SHANK3 is linked to neurodevelopmental disorder.