Three patients carrying an isodicentric (idic) Y chromosome associated
with a mosaic 45,X cell line were studied using molecular techniques.
Genotype-phenotype correlations suggested an effect of the 45,X cell
line on sexual differentiation. A relationship was established between
instability of the idic (Y) chromosome and localization of the breakp
oint on Yq, and between azoospermia and deletion of interval 6 on Yq.