Objective: To determine the clinical implications of the presence of a Y chromosome in Turner's syndrome patients with karyotype abnormalities.
Design: To investigate the presence of Y-chromosome sequences in different tissue samples.
Setting: Endocrinology outpatient clinic of a federal university in Brazil.
Patient(s): Five Turner's syndrome patients with karyotype abnormalities such as marker chromosomes, additional material, or ring chromosomes.
Intervention(s): Peripheral blood, oral epithelial cells, and hair root samples were collected.
Main outcome measure(s): The SRY gene and the DYZ3 repeat region were amplified by polymerase chain reaction followed by gel electrophoresis mobility of amplified genomic DNA, and ultraviolet visualization. Prophylactic gonadectomy was offered to the Y-positive patients.
Result(s): The analysis of the different tissues revealed that three of the five patients studied presented Y-chromosome mosaicism. These three patients underwent prophylactic gonadectomy, and in one of them, the histopathologic study of the gonads disclosed hilus cell hyperplasia and stromal luteoma with contralateral nodular hyperthecosis.
Conclusion(s): A systematic search for Y-chromosome mosaicism in Turner's syndrome patients is justified by the risk of developing gonadal tumors or androgen-producing lesions.