Prenatal identification of a Y‐chromosome deletion by Y‐specific single copy DNA probes

Abstract
A sex chromosome deletion was identified in the course of prenatal diagnosis for maternal age. Ultrasound pictures revealed male fetal sex and a comparison with the father's Y chromosome suggested that the altered chromosome might be a de novo deletion of the Y chromosome. DNA hybridization with five human Y‐specific probes shows that, among the Y‐specific sequences recognized by the probes, only two of them are absent. The normal infant, at birth, was mosaic 46, XYq‐ /46,XY.