Post mortem findings in a patient with 46,XX,fra(2)(q13).

A severely mentally retarded girl who suffered from grand mal seizures, myoclonic jerking and ataxia died at 18 years of age. Chromosome studies, before and after death revealed a fragile site on chromosome 2q13, the expression of which was greater in peripheral blood than in fibroblasts on two occasions. Post mortem findings did not reveal any abnormality which could be attributed to this fragile site.