PAK2 and Intellectual disability: Most reported 3q29 microdeletion cases included PAK2 and DLG1 genes, which are autosomal homologs of the X-linked genes PAK3 and DLG3. Haplosufficiency of PAK3 or DLG3 was reported to be associated with mental retardation.[16] Comparing our case with typical 3q29 microdeletion syndrome, our case presented an atypical 3q29 deletion with affected region ranging from 194.1 Mb to 195.8 Mb, consisting of 12 genes (Fig. 2).