Health Dictionary
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R(20) syndrome
Introduction
Ring chromosome 20, ring-shaped chromosome 20 or r(20) syndrome is a rare human chromosome abnormality where the two arms of chromosome 20 fuse to form a ring chromosome. The syndrome is associated with epileptic seizures, behaviour disorders and mental retardation.
When only one copy of chromosome 20 forms a ring, the individual suffers from ring 20 chromosomal mosaicism.
References
References
- Schinzel. A. and Niedrist, D. 2001. Chromosome imbalances associated with epilepsy. American Journal of Medical Genetics 106:119-24 PMID 11579431