19q13.11 deletion syndrome: a novel clinically recognizable genetic condition identified by array-CGH

Abstract

Deletions of chromosome 19 have rarely been reported with the exception of some patients with deletion 19q13.2 and Blackfan-Diamond syndrome due to haploinsufficiency of the RPS19 gene. Such a paucity of patients might be due to the difficulty to detect small rearrangement on this chromosome that lacks a distinct banding pattern. Array comparative genomic hybridization (array-CGH) has become a powerful tool for the detection of microdeletions and microduplications at high resolution in patients with syndromic mental retardation. By this method, we identified three interstitial overlapping 19q13.11 deletions, defining a minimal critical region of 2.87 Mb, associated with a clinically recognizable syndrome. The three patients share several major features including: pre and postnatal growth retardation with slender habitus, severe postnatal feeding difficulties, microcephaly, hypospadias, signs of ectodermal dysplasia and cutis aplasia over the posterior occiput. Interestingly, these clinical features have also been described in a previously reported patient with a 19q12q13.1 deletion. No recurrent breakpoints were identified in our patients suggesting that no-allelic homologous recombination mechanism is not involved in these rearrangements. Based on these results, we suggest that this chromosomal abnormality may represent a novel clinically recognizable microdeletion syndrome caused by haploinsufficiency of dosage sensitive genes in the 19q13.11 region.