Risk of gonadoblastoma in female patients with Y chromosome abnormalities and dysgenetic gonads

We report two female patients with gonadal dysgenesis and sex chromosome mo saicism involving the Y chromosome. Conventional karyotyping was supplement ed with fluorescent in situ hybridisation techniques in order to confirm th e presence of Y chromosomes. One patient is a phenotypic female with karyot ype 45,X/46,X,idic(Y)(q11.2). She underwent a laparoscopic gonadectomy at w hich streak ovaries without evidence of gonadoblastoma were removed. The se cond patient presented as a virilised female with karyotype 45,X/47,XYY. At laparoscopy, she was found to have mixed gonadal dysgenesis with a gonadob lastoma in situ. We recommend early gonadectomy in female children presenti ng with gonadal dysgenesis and the presence of a Y chromosome although once the gonadoblastoma locus on Y chromosome gene has been cloned it may be po ssible to identify those patients who have a low risk of developing gonadob lastoma.