3p Interstitial Deletion Including PRICKLE2 in Identical Twins With Autistic Features

Abstract

BackgroundMicrodeletion and microduplication syndromes without characteristic dysmorphic features are difficult to diagnose without chromosomal microarrays. PatientsWe describe the clinical course and genetic findings of monozygotic twins with intellectual disabilities and autistic features associated with mild facial dysmorphism and microdeletion of chromosome 3p14. ResultsThe postnatal course of the second twin was complicated by intestinal malrotation, whereas that of the first twin was unremarkable. Both twins had several mild dysmorphic features including upswept frontal hair, low-set posterior rotated ears, arched down-slanting eyebrows, prominent forehead, epicanthic folds, micrognathia, hypertelorism, broad nasal bridge, short philtrum, and camptodactyly of the bilateral fifth fingers. They had autistic features such as poor eye contact and no social smile, stereotyped behaviors, and preference for solitary play. Array comparative genomic hybridization analysis revealed de novo 6.88-Mb deletions of 3p14 (chr3: 60,472,496-67,385,119) involving 17 genes in both twins. The deleted region contained 17 genes, five of which are known or presumed to be related to central nervous system disorders: FEZF2, SYNPR, ATXN7, PRICKLE2, and MAGI1. ConclusionsWe consider that PRICKLE2 is the most likely causative gene for the autistic features exhibited by these individuals.