Cytogenetic findings in a consecutive series of 478 patients with Turner syndrome. The Leuven experience 1965-1989.

In this report, we present the cytogenetic findings in 478 patients with Turner syndrome diagnosed in Leuven in the period 1965-1989. The karyotypic anomalies are classified into seven groups: 1) classic, 45,X karyotype (52.1%); 2) mosaic 45,X/46,XX (10.9%); 3) mosaic 45,X/47,XXX and other "super-female" cell lines (4.6%); 4) isochromosomes i(Xq) and i(Xp) (16.1%); 5) ring chromosomes r(X) (4.4%); 6) other structural aberrations of the X chromosome (7.7%); and finally 7) mosaic 45,X/46,XY patients (4%). The most pertinent chromosomal findings are briefly discussed and compared with previous reported surveys on subject.