[47,XYY syndrome. Is diagnosis of significance?]

Over a 10-year period, from 1984-1995, in the Norwegian county of Vest-Agder, five patients in a paediatric clinic were diagnosed as having chromosome constitution 47,XYY. There are 1,250 males born a year in Vest-Agder. The patients were identified with bias, and not in a routine or prospective screening programme. All patients except one, a child who was diagnosed by chance at the age of one week; were admitted because of moderate conduct disorders or problems at school and striking tallness of stature. The half-brother of one of the 47,XYY boys had Klinefelter's syndrome 47,XYY. We conclude that identification of 47,XYY syndrome and information about it were of significance and help in counselling the patients and their families.