'DOUBLE MALE' – A NEW CHROMOSOME CONSTITUTION IN THE KLINEFELTER SYNDROME

Abstract

ABSTRACT 1. A Klinefelter patient is reported with the sex chromosome constitution XXYY, and the modal number of 48 chromosomes. 2. This case excludes the possibility of maternal non-disjunction as a cause. 3. The evidence of paternal and maternal errors in Klinefelter's and Turner's syndromes is discussed, and it seems that paternal errors are more common than maternal. 4. The cause of Barr body formation is discussed with preference for the theory of paternal origin of heteropycnotic sex chromosomes. This theory may explain the existence of chromatin positive Turner's and chromatin negative Klinefelter's. 5. The Y-chromosome is considered in connection with the postulated XYY-male and with the non-mosaic true hermaphrodite. 6. A simple definition of the Klinefelter syndrome is offered.