A Common Polymorphism of the SRD5A2 Gene is Not Associated With Male-to-Female and Female-to-Male Transsexualism

Completed

• Conditions: Transsexualism

• Registration Number: NCT00435513
• Lead Sponsor: Medical University of Vienna

Brief Summary

Genetic variations, i.e. polymorphisms, may be associated with gender dysphoria, e.g. transsexualism. This study aims to identify such variations.

Detailed Description

Context: Early developmental exposure of the brain to sex steroids may play a role in the etiology of transsexualism.

Objective: To assess the association between transsexualism and allele and genotype frequencies of the steroid 5-alpha reductase (SRD5A2) Val89Leu polymorphism.

Design and Patients: We performed a case-control study of 100 male-to-female (MtF) transsexuals, 47 female-to-male (FtM) transsexuals, 755 male controls, and 915 female controls. DNA was extracted from buccal swabs and genotypes were determined by polymerase chain reaction.

Results: SRD5A2 Val89Leu allele frequencies (SRD5A2 V: 137/200 \[69%\] and SRD5A2 L: 63/200 \[31%\] vs. SRD5A2 V: 1065/1510 \[71%\] and SRD5A2 L: 445/1510 \[29%\], respectively; p=0.6; Odds Ratio \[OR\] 1.10; 95% Confidence Interval \[CI\] 0.76-1.58) and genotype distributions (SRD5A2 V/V+V/L: 92/100 \[92%\] and L/L 8/100 \[8%\] vs. SRD5A2 V/V+V/L: 683/755 \[91%\] and L/L 72/755 \[9%\], respectively, p=0.7; OR 0.82; 95% CI 0.24-2.84) were not significantly different between MtF transsexuals and male controls. SRD5A2 Val89Leu allele frequencies (SRD5A2 V: 70/94 \[74%\] and SRD5A2 L: 24/94 \[26%\] vs. SRD5A2 V: 1253/1830 \[69%\] and SRD5A2 L: 573/1830 \[31%\], respectively; p=0.3; OR 0.75; 95% CI 0.45-1.26) and genotype distributions (SRD5A2 V/V+V/L: 44/47 \[93%\] and L/L 3/47 \[7%\] vs. SRD5A2 V/V+V/L: 823/915 \[90%\] and L/L 92/915 \[10%\], respectively, p=0.6; OR 0.61; 95% CI 0.11-3.32) were also not significantly different between FtM transsexuals and female controls. Of note, there was no gender-specific genotype distribution among controls.

Conclusions: The SRD5A2 Val89Leu polymorphism is not associated with transsexualism and is no candidate gene of this condition.

Study Timeline

• Study First Submitted: 2007-02-14
• Study First Submitted QC: 2007-02-14
• Study First Posted: 2007-02-15
• Study Start: 2007-03
• Primary Completion: 2008-05
• Study Completion: 2008-07
• Status Verified: 2015-05
• Last Update Submitted: 2015-05-03
• Last Update Posted: 2015-05-05

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 1770

Inclusion Criteria

• transsexual individuals as defined by DSM IV criteria

Exclusion Criteria

• unwillingness to participate

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Trial Locations

Locations (1)

University of Vienna, Vienna, Austria; 🇦🇹 Vienna, Austria