ESPE Abstracts

Background: Turner syndrome (TS) is one of the most common chromosomal aberrations resulting from the total or partial absence of one of the X chromosomes in all or a portion of cells. The presence of genetic material of the Y chromosome in TS patients is a risk factor for the development of gonadoblastoma or dysgerminoma.

Objective and hypotheses: The aim of this study was to detect the presence of fragments of the Y chromosome, which increase the risk of malignant transformation, what may be important for further proper surgical treatment (prophylactic gonadectomy).

Method: The studies were carried out using PCR method. The following genetic markers located in different regions of the Y chromosome were selected: SRY, DYZ1, DYZ3, DYS132, ZFY1, and TSPY gene located within GBY locus (gonadoblastoma locus on the Y chromosome), which is associated with the risk of the development of gonadoblastoma. Additionally, SRY gene was analyzed using direct sequencing method.

Results: 46 patients with TS with different karyotypes were studied. Based on our study 17/46 patients were chromosome Y-positive. 8/17 in the Y-positive group had Y chromosome in their karyotypes and they underwent prophylactic gonadectomy. In two of them histopathologic examination revealed gonadoblastoma and dysgerminoma respectively. Both patients were TSPY-positive. 9/17 in the Y-positive group did not have Y chromosome in their karyotypes. In 9/46 patients TSPY gene was detected – two of them did not have Y chromosome in their karyotypes. SRY gene was identified in 8/46 patients and there was no mutation in the coding region in these SRY-positive patients.

Conclusion: Molecular tests for the presence of genetic material of the Y chromosome in TS, particularly TSPY, are the most precise ones, and may serve as important tools in cancer risk prediction as well as risk of virilization.