Chromosome 1p terminal deletion: Report of new findings and confirmation of two characteristic phenotypes

Abstract

We report three unrelated patients with small terminal deletions involving lp36.22→pter that occurred de novo and compare our patients to the 10 previously reported cases. Although ourpatients have an identical cytogenetic deletion, patients 1 and 2 share similar clinical features that differ subsantially from patient 3. Our patients confirm the existence of two characteristic phenotypes in lp36.22→pter deletion. Both phenotypes share somedysmorphic features, but are differentiated by characteristics of growth failure versus macrosomia. In addition, we report the newfinding of cardiomyopathy and hydrocephalus in the phenotype associated with growth filure. It is possible that different phenotypic subgroups may exist because of differences in the parental origins of the deleted chromosome or of variations in undetectable amounts of genetic material.