Microdeletions and Microduplications: Mechanism

Bernice E Morrow, Albert Einstein College of Medicine, Bronx, New York, USA

Published online: January 2006

DOI: 10.1038/npg.els.0005789

Microdeletions and microduplications in the genome are caused by chromosome misalignment between blocks of region-specific low copy repeats and result in genomic disorders.

Keywords: chromosome rearrangements; genomic disorders; 22q11; low copy repeats; congenital anomaly disorders; homologous recombination

Figure 1. Models for homologous recombination (HR) events involving region-specific low copy repeats (LCRs). (a) Intrachromosomal HR events between two LCRs can generate a deletion by excision of an intrachromatidal loop. (b) Interchromosomal HR events between two LCRs on two homologous chromosomes can generate a duplication and a deletion.
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 References
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 Further Reading
    Bailey JA, Yavor AM, Viggiano L, et al. (2002) Human-specific duplication and mosaic transcripts: the recent paralogous structure of chromosome 22. American Journal of Human Genetics 70: 83–100.
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Related Sub-Topics:

Replication and Recombination | Mutational Mechanisms of Genetic Disease | Gene and Genome Structure and Organisation | Chromosomal Disorders | Genomic Disorders | Chromosomes and Chromatin Modifications | DNA Structure and Function
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Article Title: Microdeletions and Microduplications: Mechanism
 
How to Cite close
Morrow, Bernice E(Jan 2006) Microdeletions and Microduplications: Mechanism. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0005789]