Source:http://linkedlifedata.com/resource/umls/id/C0265482
JABL: A rare chromosomal anomaly in which both ends of chromosome 20 have been lost (deletion) and the two broken ends have reunited to form a ring-shaped figure. Seizures, behavior problems, variable degrees of mental retardation and minor anomalies are the most common clinical characteristics but there does not appear to be a constant pattern of dysmorphic signs.