title: Single gene microdeletions and microduplication of 3p26.3 in three unrelated families: CNTN6 as a new candidate gene for intellectual disability.
abstract: BACKGROUND
  Detection of submicroscopic chromosomal alterations in patients with a idiopathic intellectual disability (ID) allows significant improvement in delineation of the regions of the genome that are associated with brain development and function. However, these chromosomal regions usually contain several protein-coding genes and regulatory elements, complicating the understanding of genotype-phenotype correlations. We report two siblings with ID and an unrelated patient with atypical autism who had 3p26.3 microdeletions and one intellectually disabled patient with a 3p26.3 microduplication encompassing only the CNTN6 gene.
  
  
  RESULTS
  Two 295.1-kb microdeletions and one 766.1-kb microduplication of 3p26.3 involving a single gene, CNTN6, were identified with an Agilent 60K array. Another 271.9-kb microdeletion of 3p26.3 was detected using an Affymetrix CytoScan HD chromosome microarray platform. The CHL1 and CNTN4 genes, although adjacent to the CNTN6 gene, were not affected in either of these patients.
  
  
  CONCLUSIONS
  The protein encoded by CNTN6 is a member of the immunoglobulin superfamily and functions as a cell adhesion molecule that is involved in the formation of axon connections in the developing nervous system. Our results indicate that CNTN6 may be a candidate gene for ID.
authors.affiliation: Laboratory of Cytogenetics, Institute of Medical Genetics, 10 Nab. Ushaiki, 634050 Tomsk, Russia.
authors.forename: Anna A
authors.initials: AA
authors.lastname: Kashevarova
authors.affiliation: Laboratory of Hereditary Pathology, Institute of Medical Genetics, Tomsk, Russia ; Department of Medical Genetics, Siberian State Medical University, Tomsk, Russia.
authors.forename: Lyudmila P
authors.initials: LP
authors.lastname: Nazarenko
authors.affiliation: Private Pediatric Clinics "Bornelaegen Aarhus", Aarhus, Denmark.
authors.forename: Soren
authors.initials: S
authors.lastname: Schultz-Pedersen
authors.affiliation: Laboratory of Cytogenetics, Institute of Medical Genetics, 10 Nab. Ushaiki, 634050 Tomsk, Russia ; Laboratory of Human Ontogenetics, Tomsk State University, Tomsk, Russia.
authors.forename: Nikolay A
authors.initials: NA
authors.lastname: Skryabin
authors.affiliation: Laboratory of Hereditary Pathology, Institute of Medical Genetics, Tomsk, Russia ; Department of Medical Genetics, Siberian State Medical University, Tomsk, Russia.
authors.forename: Olga A
authors.initials: OA
authors.lastname: Salyukova
authors.affiliation: Laboratory of Hereditary Pathology, Institute of Medical Genetics, Tomsk, Russia.
authors.forename: Nataliya N
authors.initials: NN
authors.lastname: Chechetkina
authors.affiliation: Laboratory of Cytogenetics, Institute of Medical Genetics, 10 Nab. Ushaiki, 634050 Tomsk, Russia.
authors.forename: Ekaterina N
authors.initials: EN
authors.lastname: Tolmacheva
authors.affiliation: Genetic Clinic, Institute of Medical Genetics, Tomsk, Russia.
authors.forename: Aleksey A
authors.initials: AA
authors.lastname: Rudko
authors.affiliation: Unit of Medical Genetics, Department of Gynecology, Obstetrics and Pediatrics, University of Bologna, Bologna, Italy.
authors.forename: Pamela
authors.initials: P
authors.lastname: Magini
authors.affiliation: Unit of Medical Genetics, Department of Gynecology, Obstetrics and Pediatrics, University of Bologna, Bologna, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Graziano
authors.affiliation: Unit of Medical Genetics, Department of Gynecology, Obstetrics and Pediatrics, University of Bologna, Bologna, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Romeo
authors.affiliation: Department of Clinical Genetics, Level 2, Laboratory Medicine Building, Southern General Hospital, Glasgow, G51 4TF Scotland UK.
authors.forename: Shelagh
authors.initials: S
authors.lastname: Joss
authors.affiliation: Applied Human Molecular Genetics, Kennedy Center, Department of Clinical Genetics, Copenhagen University Hospital, Rigshospitalet, Copenhagen Denmark.
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Tümer
authors.affiliation: Laboratory of Cytogenetics, Institute of Medical Genetics, 10 Nab. Ushaiki, 634050 Tomsk, Russia ; Department of Medical Genetics, Siberian State Medical University, Tomsk, Russia.
authors.forename: Igor N
authors.initials: IN
authors.lastname: Lebedev
keywords: 3p26.3 microdeletion; 3p26.3 microduplication; CNTN6; Intellectual disability; Reciprocal microdeletions/microduplications