Background: Of the fewer than 100 cases reported within the literature of constitutional deletions involving the long arm of chromosome 6, only five have been characterized using high-resolution microarray analysis. Reported 6q deletion patients show a high incidence of mental retardation, ear anomalies, hypotonia, and postnatal growth retardation.
Results: We report a 16-month-old male presenting with developmental delay and dysmorphic features who was found by array-based comparative genomic hybridization (aCGH) to have a ~2.16 Mb de novo deletion within chromosome band 6q16.1 that encompasses only two genes. Expression studies of the mouse homologue of one of the genes, the ephrin receptor 7 gene (EPHA7), have shown the gene functions during murine embryogenesis to form cortical domains, determine brain size and shape, and play a role in development of the central nervous system (CNS).
Discussion: Our results suggest that deletion of EPHA7 plays a role in the neurologic and dysmorphic features, including developmental delay, hypotonia, and ear malformations, observed in some 6q deletion patients.