title: Clinico-radiological and molecular characterization of a child with ring chromosome 2 presenting growth failure, microcephaly, kidney and brain malformations.
abstract: BACKGROUND
  Ring chromosome 2 is a rare constitutional abnormality that generally occurs de novo. About 14 cases have been described to date, but the vast majority of papers report exclusively conventional cytogenetic investigations and only two have been characterized by array-CGH.
  
  
  RESULTS
  Here we describe the clinical, neuroradiological, and molecular features of a 5-year-old boy harbouring a ring chromosome 2 presenting with severe growth failure, facial and bone dysmorphisms, microcephaly, and renal malformation. Brain MR with diffusion tensor imaging revealed simplified cortical gyration, pontine hypoplasia, and abnormally thick posterior corpus callosum, suggesting an underlying axonal guidance defect. Cytogenetic investigations showed a karyotype with a ring chromosome 2 and FISH analysis with subtelomeric probes revealed the absence of signals on both arms. These results were confirmed by array-CGH showing terminal deletions on 2p25.3 (~439 kb) and 2q37.3 (~3.4 Mb).
  
  
  CONCLUSIONS
  Our report describes a new patient with a ring chromosome 2 completely characterised by array-CGH providing additional information useful not only to study genotype-phenotype correlation but also to validate the role of already reported candidate genes and to suggest novel ones which could improve our understanding of the clinical features associated with ring chromosome 2.
authors.affiliation: Neuroradiology Unit, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Mariasavina
authors.initials: M
authors.lastname: Severino
authors.affiliation: Pediatric Pulmonology and Allergy Unit, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Accogli
authors.affiliation: Laboratorio di Citogenetica, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Gimelli
authors.affiliation: Neuroradiology Unit, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Rossi
authors.affiliation: Anesthesiology Unit, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Kotzeva
authors.affiliation: Pediatria II, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Maja
authors.initials: M
authors.lastname: Di Rocco
authors.affiliation: Laboratorio di Citogenetica, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Ronchetto
authors.affiliation: Laboratorio di Citogenetica, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Cuoco
authors.affiliation: Laboratorio di Citogenetica, Istituto Giannina Gaslini, Genoa, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Tassano
keywords: 2p25.3 deletion; 2q37.3 deletion; Array-CGH; Brain MRI; Diffusion tensor imaging; Ring chromosome 2