The (CA)n Polymorphism of ERβ Gene is Associated with FtM Transsexualism. (26th November 2013)

• Record Type: Journal Article
• Authors: Fernández, Rosa; Esteva, Isabel; Gómez‐Gil, Esther; Rumbo, Teresa; Almaraz, Mari Cruz; Roda, Ester; Haro‐Mora, Juan‐Jesús; Guillamón, Antonio; Pásaro, Eduardo
• Is Part Of: Journal of sexual medicine. Volume 11:Number 3(2014:Mar.)
• Page Start: 720
• Page End: 728
• Publication Date: 2013-11-26
• Subjects: Sexual disorders -- Periodicals; Sex -- Periodicals; Sexual health -- Periodicals; 616.69005
• DOI: 10.1111/jsm.12398
• Languages: English
• ISSNs: 1743-6095

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <sec id="jsm12398-sec-0001" sec-type="section"> <title>Introduction</title> <p>Transsexualism is a gender identity disorder with a multifactorial etiology. Neurodevelopmental processes and genetic factors seem to be implicated.</p> </sec> <sec id="jsm12398-sec-0002" sec-type="section"> <title>Aim</title> <p>The aim of this study was to investigate the possible influence of the sex hormone‐related genes <italic>ER</italic><italic>β</italic> (estrogen receptor β), <italic>AR</italic> (androgen receptor), and <italic>CYP19A1</italic> (aromatase) in the etiology of female‐to‐male (FtM) transsexualism.</p> </sec> <sec id="jsm12398-sec-0003" sec-type="section"> <title>Methods</title> <p>In 273 FtMs and 371 control females, we carried out a molecular analysis of three variable regions: the CA repeats in intron 5 of <italic>ER</italic><italic>β</italic>; the CAG repeats in exon 1 of <italic>AR</italic>, and the TTTA repeats in intron 4 of <italic>CYP19A1</italic>.</p> </sec> <sec id="jsm12398-sec-0004" sec-type="section"> <title>Main Outcome Measures</title> <p>We investigated the possible influence of genotype on transsexualism by performing a molecular analysis of the variable regions of genes <italic>ER</italic><italic>β</italic>, <italic>AR</italic>, and <italic>CYP19A1</italic> in 644 individuals (FtMs and control females).</p> </sec> <sec id="jsm12398-sec-0005" sec-type="section"> <title>Results</title> <p>FtMs differed significantly from control group with respect to the median repeat length polymorphism <italic>ER</italic><italic>β</italic> (<italic>P</italic> = 0.002) but not with respect to the length of the other two studied polymorphisms. The repeat numbers in <italic>ER</italic><italic>β</italic> were significantly higher in FtMs than in control group, and the likelihood of developing transsexualism was higher (odds ratio: 2.001 [1.15–3.46]) in the subjects with the genotype homozygous for long alleles.</p> </sec> <sec id="jsm12398-sec-0006" sec-type="section"> <title>Conclusions</title> <p>There is an association between the <italic>ER</italic><italic>β</italic> gene and FtM transsexualism. Our data support the finding that <italic>ER</italic><italic>β</italic> function is directly proportional to the size of the analyzed polymorphism, so a greater number of repeats implies greater transcription activation, possibly by increasing the function of the complex hormone ERβ receptor and thereby encouraging less feminization or a defeminization of the female brain and behavior. <bold>Fernández R, Esteva I, Gómez‐Gil E, Rumbo T, Almaraz MC, Roda E, Haro‐Mora JJ, Guillamón A, Pásaro E. The (CA)n polymorphism of <italic>ERβ</italic> gene is associated with FtM transsexualism. J Sex Med 2014;11:720–728.</bold></p> </sec> </abstract>