SRY GENE SCREENING IN TURNER SYNDROME BY POIYMERASE CHAIN REACTION (PCR)

Abstract

The association between gonadal tumor and Y chromosome material in patients with dysgenetic gonads is well defined. Cytogenetic analysis sometimes is unable to detect low mosaicisms or to identify the origin of ring/maker chromosome fragments. Recently molecular techniques have determined Y chromosomal material in Turner syndrome. We studied 27 patients with Turner syndrome by PCR technique using XES10 e XSE11 primers that amplify the complete sex determining region (780bp) of the Y-chromosome gene (SRY) with the use of the following program: 32 cycles (94°C, 1 min, 55°C, 1 min and 72°C, 2 min). Only one patient had mild virilization (clitoromegaly). Cytoaenetic analysis revealed: 16 cases 45, X, 6 cases 45, X + mar, 4 cases 45, X/46, XX, 1 case 45, X/46, X die (Y) (qter → p11::p11 → qter) by C and G banding techniques. PCS amplification of the SRY gene was positive in 3 patients (11% of the cases). Two of these were 45, X, + mar (including the patient with clitoromegaly), and the third patient was 45, X/46, X die (Y). Conclusion: Molecular techniques are faster and more sensitive than cytogenetic studies to detect fragments of Y chromosome. These findings further underline the relevance of performing molecular studies in patients with Turner Syndrome, which may help to define appropriate therapeutic strategies.