Interstitial deletion of the short arm of chromosome 1 (1p13.1p21.1) in a girl with mental retardation, short stature and colobomata.

Interstitial deletions on the short arm of chromosome 1 are rare. We describe a girl with severe mental retardation, short stature and dysmorphic features including colobomata where high-resolution comparative genomic hybridization revealed an interstitial deletion with breakpoints in band 1p13.1 and 1p21.1. The deletion was further characterized by real-time polymerase chain reaction. We hypothesize that haploinsufficiency of WNT2B (wingless-type MMTV integration site family, member 2B) and NTNG1 (Netrin G1) contributed to the patient's phenotype.