Korean J Pediatr.  2005 Jan;48(1):108-111.

A Case of Ring Chromosome 20 with Mental Retardation and Epilepsy

• Jung YK
• Lee GH

Abstract

Ring chromosome 20 mosaicism [r(20)] is a rare chromosomal anomaly associated with minor dysmorphism, mental retardation, autistic behavior, and intractable epilepsy. The proposed mechanism of ring formation is breakage of both short and long arms of a chromosome with subsequent end-to- end fusion. We encountered an 18-month-old boy who presented with developmental delay and mental retardation with seizure episodes, but showed normal brain magnetic resonance imaging. Chromosome study from peripheral blood showed 46,XY, r(20)(p13q13.3) karyotype. The authors report a case of ring chromosome 20 with mental retardation and epilepsy, with a review of the literature.

Keyword

Ring chromosome 20; Epilepsy; Mental retardation

MeSH Terms

Arm
Brain
Epilepsy*
Humans
Infant
Intellectual Disability*
Karyotype
Magnetic Resonance Imaging
Male
Mosaicism
Ring Chromosomes*
Seizures