Genes of the SH3 and multiple ankyrin repeat domains (SHANK) family encode a class of crucial multifunctional scaffolding proteins, whose disruption is highly associated with autism spectrum disorder (ASD) and more specifically the Phelan-McDermid syndrome (PMDS), which results from SHANK3-haploinsufficiency or heterozygous SHANK3 variants that alter function. Here, SHANK2 is linked to Phelan-McDermid syndrome.