The concurrence of Klinefelter syndrome and fragile X syndrome.

In this paper we report on a third patient with Klinefelter syndrome and fragile X. In the Leuven experience the simultaneous occurrence of both conditions is 1:155 (3 fra(X) positive Klinefelter patients in a total number of 465 fra(X) positive males), a concurrence much higher than expected by chance considering the frequency of both conditions.