Microdeletions and Microduplications: Mechanism


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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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.

Emanuel BS and Shaikh TH (2001) Segmental duplications: an ‘expanding’ role in genomic instability and disease [review]. Nature Reviews Genetics 2: 791–800.

Stankiewicz P and Lupski JR (2002) Genome architecture, rearrangements and genomic disorders. Trends in Genetics 18: 74–82.

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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]