Molecular analysis of 20 patients with 2q37.3 monosomy: Definition of minimum deletion intervals for key phenotypes

Abstract

This detailed analysis of 20 patients with 2q37.3 monosomy has, for the first time, allowed minimal deletion intervals to be defined for all the major phenotypes of the syndrome. However, there is striking phenotypic variability and it is clear that the size and extent of the deleted region cannot be used as a predictor of the likely phenotype in the patient. As increasing numbers of small deletions are detected by more widespread use of subtelomeric FISH, this presents a challenge for clinicians in trying to determine the likely prognosis for a young proband. Ultimately, therefore, the real challenge is to identify not only the gene(s) on 2q37 responsible for the phenotypes in these patients, but also the modifiers, be they genetic, epigenetic, or environmental, that contribute to the phenotypic variability between patients with similar breakpoints. Only then can we begin to give more precise prognostic information to the parents of a child newly-diagnosed with a 2q37.3 deletion.