Diplo-Y Syndrome (47,XYY Syndrome) [Q98.5]
Dipl.-Biol. Uwe Heinrich
The XYY syndrome has an incidence of approx. 1 in 1,000 in male newborns. Usually, a 47,XYY karyotype is found, in rare cases X and Y polysomies. Characteristically, patients are of above average body size, do usually not exhibit other physical abnormalities and have a normal fertility. The IQ is usually normal. Motor development may be slightly delayed. Reading and speaking problems may result in emotional disorders and a low frustration tolerance. Therefore, psychological and pedagogical support during childhood can be indicated. Scientific studies show that in stable family environments, boys and men with an XYY constellation do not tend to exhibit behavioural disorders more often than others. Offspring of XYY men have no higher risk for gonosomal aneuploidy.