The XYY syndrome in an adolescent male exhibiting prominent behavioral problems

Abstract
From 1961 until 1971, a male patient of average intelligence underwent clinical and psychiatric investigations in two hospitals for rather prominent behavioral problems affecting learning. The patient was of excessive height and showed abnormally aggressive conduct. Electroencephalogram examinations showed a cyclic pattern in which neurological, primarily coordination, problems were evident. Cytological examination revealed an XYY chromosome constitution. An incident fluorescent system was more effective than a transmitted one in bringing about fluorescence of the Y chromosome.