Psychological characteristics associated with XYY sex-chromosome complement in a state mental hospital.

Abstract

In a recent survey of males detained in a State hospital for dangerous, violent and criminal psychiatric patients, seven subjects with an XYY sex-chromosome constitution were discovered (Jacobs et al., 1965). Further investigation (Price et al., 1966) yielded two more patients with this abnormality. Psychological testing of these same patients was undertaken in order to detect cognitive or clinical features which distinguish them from other men in the same hospital.