Please use this identifier to cite or link to this item:
https://hdl.handle.net/2440/66018
Citations | ||
Scopus | Web of Science® | Altmetric |
---|---|---|
?
|
?
|
Type: | Journal article |
Title: | Molecular analysis of ring chromosome 20 syndrome reveals two distinct groups of patients |
Author: | Conlin, L. Kramer, W. Hutchinson, A. Li, X. Riethman, H. Hakonarson, H. Mulley, J. Scheffer, I. Berkovic, S. Hosain, S. Spinner, N. |
Citation: | Journal of Medical Genetics, 2011; 48(1):1-9 |
Publisher: | British Med Journal Publ Group |
Issue Date: | 2011 |
ISSN: | 0022-2593 1468-6244 |
Statement of Responsibility: | Laura K Conlin, Whitney Kramer, Anne L Hutchinson, Xia Li, Harold Riethman, Hakon Hakonarson, John C Mulley, Ingrid E Scheffer, Samuel F Berkovic, Syed A Hosain and Nancy B Spinner |
Abstract: | Background The ring chromosome 20 syndrome (R20) is a rare genetic disorder associated with a refractory electroclinical epilepsy syndrome and variably expressed comorbidities of intellectual disability and dysmorphism. Methods To understand the structure and composition of the ring chromosome 20 (r(20)) in this patient cohort, blood specimens from 28 affected individuals were analysed by cytogenetic, fluorescence in situ hybridisation, and/or high resolution whole genome single nucleotide polymorphism array analysis. Results These studies revealed two distinct groups of patients. Group 1 (N=21) was mosaic for the r(20) and a normal cell line with no detectable deletions or duplications of chromosome 20 in either cell line. The mosaic nature of these rings suggests a postzygotic origin with formation of the ring by fusion of the telomeric regions with no apparent loss of subtelomeric or telomeric DNA. Group 2 (N=7) had non-mosaic ring chromosomes with a deletion at one or both ends of the chromosome, near the ring fusion point. The non-mosaic nature of these rings is consistent with a meiotic origin. The age of onset of seizures was significantly lower in the non-mosaic patients (group 2, median age of onset 2.1 years) than in the mosaic patients (group 1, median age of onset 6.0 years). Patients from group 2 had more extensive comorbidities. Conclusions These studies demonstrate that r(20) is molecularly heterogeneous and formed by two distinct mechanisms, which, in turn, produce different phenotypic spectrums. |
Keywords: | Cells, Cultured Chromosomes, Human, Pair 20 Ring Chromosomes Humans Seizures Chromosome Deletion Syndrome Chromosome Banding In Situ Hybridization, Fluorescence Age of Onset Polymorphism, Single Nucleotide |
Rights: | Copyright © 2011 by the BMJ Publishing Group Ltd. All rights reserved |
DOI: | 10.1136/jmg.2010.080382 |
Published version: | http://dx.doi.org/10.1136/jmg.2010.080382 |
Appears in Collections: | Aurora harvest Molecular and Biomedical Science publications |
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.