Original Investigations

Human Genetics

, Volume 80, Issue 1, pp 16-22

First online:

X-chromosome polysomy in the male

The Leuven experience 1966–1987
  • Alice KleczkowskaAffiliated withCentre for Human Genetics, U.Z. Gasthuisberg
  • , Jean-Pierre FrynsAffiliated withCentre for Human Genetics, U.Z. Gasthuisberg
  • , Herman Van den BergheAffiliated withCentre for Human Genetics, U.Z. Gasthuisberg

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A review of 569 male patients with X-chromosome polysomies (544 Klinefelter and 25 patients with other types of X-chromosome polysomy) is presented here. These patients were detected among the 77000 persons karyotyped in the Leuven cytogenetic center between the years 1966 and 1987. In the group of 544 Klinefelter patients special attention was paid to (1) the age at diagnosis, (2) social and marital status of the postpubertal males, (3) physical and intellectual abilities of the prepubertal boys, (4) delineation of the concurrence of Klinefelter syndrome and fragile X syndrome, and (5) the frequency of malignancies. In 25 patients with other X-chromosome polysomies (2 n≥48 chromosomes) genotype/phenotype correlation is reviewed, especially for the patients with 48,XXYY and 49,XXXXY karyotypes. Finally, double aneuploidy and rare structural X-chromosome aberrations are briefly discussed.