Ectodermal dysplasia-like syndrome with mental retardation due to contiguous gene deletion: further clinical and molecular delineation of del(2q32) syndrome

Abstract

We report on a patient with an interstitial deletion of the long arm of chromosome 2 at 2q31.2q33.2. She had prenatal and postnatal growth retardation, microcephaly, facial dysmorphism, cleft palate, camptodactyly, bilateral talipes equinovarus, severe intellectual disability, and ectodermal anomalies. She showed thin, atrophic skin, sparse, brittle, slowly growing hair, oligodontia with abnormally shaped teeth, normal sweating, and normal fingernails, consistent with a diagnosis of ectodermal dysplasia. Array CGH analysis (Agilent 44K) showed the deletion to span 26 Mb, between cytogenetic bands 2q31.2 and 2q33. The deletion leads to hemizygosity for the HOXD cluster and its regulatory elements, COL3A1/COL5A2, GTF3C3, CASP8, CASP10, and SABT2 could perhaps interfere with long range control of DLX1 and DLX2 expression. This girl confirms the existence of a clinically recognizable 2q32 microdeletion syndrome, as recently delineated by Van Buggenhout et al. and confirms a novel putative locus for ectodermal dysplasia on chromosome 2q31q33. We recommend considering cytogenetic and/or molecular screening for del(2q32) in patients with developmental disability and ectodermal dysplasia-like phenotype, including thin skin, oligodontia, dysplastic teeth, and sparse hair.