Array‐CGH and clinical characterization in a patient with subtelomeric 6p deletion without ocular dysgenesis

Abstract

Subtelomeric terminal 6p deletion has been recognized as a clinically identifiable syndrome including facial dysmorphism, malformation of the anterior eye chamber, hearing loss, heart defects, and developmental delay. Genotype-phenotype correlations of previously published patients have strongly suggested anterior eye segment anomalies as one of the major malformations of the syndrome if the critical 6p25 region contains the FOXC 1 gene. In addition, the presence in this region of one or more genes involved in hearing loss has been hypothesized. We report a patient with a 47,XYY karyotype and submicroscopic terminal 6p deletion. Further characterization of the deletion with array comparative genome hybridization also revealed a cryptic microduplication on chromosome 19. The patient showed dysmorphic features, neuromotor retardation, and profound language impairment, in absence of hearing loss and structural eye anomalies. As far as we know this is the first reported terminal 6p25.1 deletion case without eye dysgenesis precisely characterized by array-CGH. Our result suggests that the genes in this region may not be obvious candidates for hearing loss and demonstrate the need for further elucidation of the function of the genes involved in eye developmental processes.