Published online by Cambridge University Press: 09 July 2009
A study of four 47XYY subjects and their families is reported. These subjects were all exceptionally tall; were mostly of good intelligence and from intelligent families; and all had a history of delinquency or criminality, although they came from respectable homes. Evidence is presented, however, to suggest that both adverse environmental influences and constitutional factors other than their supernumary chromosomes nevertheless operated in these cases, indicating that their deviant behaviour need not be directly related to their chromosomal abnormality. The implications of these findings are discussed with respect especially to their bearing on conclusions drawn in the literature on the XYY syndrome.
This work was supported in part by a grant to D. R. Pitcher from the Medical Research Council.