Polymerase Chain Reaction as a Diagnostic Complement for Turner Syndrome and Gonadal Dysgenesis 46,XX in the Unified Health System of Alagoas.
Gonadal Developmental Disorders; Turner Syndrome; Y chromosome; Gonadal Dysgenesis 46,XX.
Introduction: Gonadal Dysgenesis (GD) is classified as Sex Development Disorder/Differences (DSD) and is characterized by impaired gonad development. GD can be classified as Complete Gonadal Dysgenesis (GDC), Mixed Dysgenesis (GDM) or Partial Gonadal Dysgenesis (GDP). Turner Syndrome (TS), related to alterations in the X chromosome, is one of the most prevalent syndromes in females and impairs gonadal development. Individuals with GD and TS are at increased risk for developing germline tumors due to abnormalities in gonad organogenesis, which are aggravated by the presence of Y chromosome markers. Objective: To investigate Y chromosome markers in cases diagnosed with TS and GD 46,XX treated at the SUS of Alagoas. Methods: This is a cross-sectional, observational, descriptive study with a sample consisting of individuals with a clinical and cytogenetic diagnosis of TS and GD 46,XX, regardless of age, treated at the SUS in Alagoas between May 2008 and May 2023. To describe the sample, medical records with sociodemographic, clinical, cytogenetic and molecular data were analyzed. The molecular investigation of Y markers took place through Conventional Polymerase Chain Reaction (PCR) and NESTED. All results were organized in an Excel spreadsheet for later analysis. Results: From a sample of 233 cases of DSD treated at the Clinical Genetics Service of the Professor Alberto Antunes University Hospital (SGC/HUPAA), 12 had GD 46.XX and 34 had TS. All cases with 46.XY karyotypes and cases with 46.XX karyotypes without clinical characteristics of DG and TS were excluded. The sample of this study consisted of 46 participants. Of these, 60.87% of the participants came from the interior of Alagoas, 32.61% from the capital and 6.52% did not have information on origin. The mean age for the first visit was 16.91 years, with primary amenorrhea, short stature, and delayed development of secondary sex characteristics. 73.91% of the cases were clinically diagnosed with TS, while 26.09% were diagnosed with Gonadal Dysgenesis 46.XX. The presence of Y chromosome markers was observed in 4.35% of the sample and 95.35% did not present the investigated markers. Discussion: According to the literature, about 4-60% of TS cases may have Y-specific sequences in their chromosomal constitution. On the other hand, for DG 46,XX, these data are not presented in the literature. Cases with DG 46,XX and ST, which have Y chromosome markers in their chromosomal constitution, have an increased risk for the development of gonadal tumors and prophylactic gonadectomy is indicated in these cases. Conclusion: The investigation of Y markers was performed in 34 individuals with clinical and cytogenetic diagnosis of TS and 12 individuals with GD 46,XX. PCRs revealed Y chromosome markers in 2 participants of the sample, both with TS. Participants who did not present Y markers remain under investigation.