A novel duplication of chromosome (13)(q14.1q21.3) in a patient with mental retardation and microcephaly.

We report on a mentally retarded female with behavioural problems, microcephaly, mild facial dysmorphisms, short stature and small hands with thin fingers due to a de novo partial duplication within the long arm of chromosome 13(q14.1q21.3). She was primarily referred to the outpatient department of neuropsychiatry because of short lasting psychotic episodes. No formal psychiatric diagnosis was made and the behavioural problems appeared the result of anxieties provoked by novel situations, enhanced by the intellectual disability. To the author's knowledge, this duplication has not been published previously and it is considered causative of the phenotype.