An interstitial deletion of chromosome 7 at band q21: A case report and review

Department of Medical Genetics, University Hospital Ghent, Ghent, BelgiumWe report on a girl with moderate developmentaldelay and mild dysmorphic features. Cytogeneticinvestigations revealed a de novo interstitialdeletion at the proximal dark band on the longarmofchromosome7(7q21.1-q21.3)inallanalyzedG-banded metaphases of lymphocytes and fibro-blasts. Fluorescence in situ hybridization (FISH)and molecular studies defined the breakpoints at7q21.11 and 7q21.3 on the paternal chromosome 7,with the proximal deletion breakpoint betweenthe elastin gene (localized at 7q11.23) andD7S2517, and the distal breakpoint betweenD7S652 and the COL1A2 gene (localized at7q21.3-q22.1). Deletions of interstitial segmentsat the proximal long arm of chromosome 7 at q21are relatively rare. The karyotype–phenotypecorrelation of these patients is reviewed anddiscussed. The clinical findings of patients with adeletion at 7q21 significantly overlap with thoseof patients with maternal uniparental disomy ofchromosome 7 (matUPD(7)) and Silver–Russellsyndrome (SRS, OMIM 180860). Therefore, 7q21might be considered a candidate chromosomalregion for matUPD(7) and SRS.