1. Academic Validation
  2. Recurrent rearrangements of chromosome 1q21.1 and variable pediatric phenotypes

Recurrent rearrangements of chromosome 1q21.1 and variable pediatric phenotypes

  • N Engl J Med. 2008 Oct 16;359(16):1685-99. doi: 10.1056/NEJMoa0805384.
Heather C Mefford 1 Andrew J Sharp Carl Baker Andy Itsara Zhaoshi Jiang Karen Buysse Shuwen Huang Viv K Maloney John A Crolla Diana Baralle Amanda Collins Catherine Mercer Koen Norga Thomy de Ravel Koen Devriendt Ernie M H F Bongers Nicole de Leeuw William Reardon Stefania Gimelli Frederique Bena Raoul C Hennekam Alison Male Lorraine Gaunt Jill Clayton-Smith Ingrid Simonic Soo Mi Park Sarju G Mehta Serena Nik-Zainal C Geoffrey Woods Helen V Firth Georgina Parkin Marco Fichera Santina Reitano Mariangela Lo Giudice Kelly E Li Iris Casuga Adam Broomer Bernard Conrad Markus Schwerzmann Lorenz Räber Sabina Gallati Pasquale Striano Antonietta Coppola John L Tolmie Edward S Tobias Chris Lilley Lluis Armengol Yves Spysschaert Patrick Verloo Anja De Coene Linde Goossens Geert Mortier Frank Speleman Ellen van Binsbergen Marcel R Nelen Ron Hochstenbach Martin Poot Louise Gallagher Michael Gill Jon McClellan Mary-Claire King Regina Regan Cindy Skinner Roger E Stevenson Stylianos E Antonarakis Caifu Chen Xavier Estivill Björn Menten Giorgio Gimelli Susan Gribble Stuart Schwartz James S Sutcliffe Tom Walsh Samantha J L Knight Jonathan Sebat Corrado Romano Charles E Schwartz Joris A Veltman Bert B A de Vries Joris R Vermeesch John C K Barber Lionel Willatt May Tassabehji Evan E Eichler
Affiliations

Affiliation

  • 1 University of Washington School of Medicine, Seattle 98195, USA.
Abstract

Background: Duplications and deletions in the human genome can cause disease or predispose persons to disease. Advances in technologies to detect these changes allow for the routine identification of submicroscopic imbalances in large numbers of patients.

Methods: We tested for the presence of microdeletions and microduplications at a specific region of chromosome 1q21.1 in two groups of patients with unexplained mental retardation, autism, or congenital anomalies and in unaffected persons.

Results: We identified 25 persons with a recurrent 1.35-Mb deletion within 1q21.1 from screening 5218 patients. The microdeletions had arisen de novo in eight patients, were inherited from a mildly affected parent in three patients, were inherited from an apparently unaffected parent in six patients, and were of unknown inheritance in eight patients. The deletion was absent in a series of 4737 control persons (P=1.1x10(-7)). We found considerable variability in the level of phenotypic expression of the microdeletion; phenotypes included mild-to-moderate mental retardation, microcephaly, cardiac abnormalities, and cataracts. The reciprocal duplication was enriched in nine children with mental retardation or autism spectrum disorder and other variable features (P=0.02). We identified three deletions and three duplications of the 1q21.1 region in an independent sample of 788 patients with mental retardation and congenital anomalies.

Conclusions: We have identified recurrent molecular lesions that elude syndromic classification and whose disease manifestations must be considered in a broader context of development as opposed to being assigned to a specific disease. Clinical diagnosis in patients with these lesions may be most readily achieved on the basis of genotype rather than phenotype.

Figures