ANÁLISE DO POLIMOFISMO RsaI DO GENE RECEPTOR BETA ESTRÓGENO (REβ) EM MULHERES COM ENDOMETRIOSE

Abstract

Endometriosis is defined by the appearance of foci of endometrial tissue with glandular features and / or stromal identical to the uterine cavity at locations other than the endometrium. And these foci of tissue are usually functioning and sensitive to the action of hormones showing a strong genetic component to disease correlated with several polymorphisms. It focuses primarily on women of reproductive age. Is present in 10% of general population and infertility in 30% to 40% of cases. The degree of involvement of endometriosis is based on a points system proposed by the American Society for Reproductive Medicine (1978), based on the findings of laparoscopy. The action of estrogen is mediated by intracellular receptors that, with the binding of ligands are translocated to the nucleus where it activates gene transcription and REβ is one of the isoforms of these receptors. The REβ gene was mapped and located on the long arm of chromosome 14 in the loco 2 among subloco 23:24 (14q22-24) and the polymorphism consists of a silent G1082A transition in the binding domain of exon 5. The intent of this study was to determine the frequency of the RsaI polymorphism of the gene REβ in two groups of patients with endometriosis and without symptoms. The study included 54 samples of peripheral blood of women with endometriosis from a referral center in laparoscopy and infertility in the city of Goiania (FÉRTILE) and 46 peripheral blood samples from women without endometriosis clinic called the control group. Later the group with endometriosis were divided into two groups fertile (n = 25) and infertile (n = 27). The RsaI polymorphism of the gene REβ (AA, AG, GG) and the gene p53 in codon 72 was assessed using PCR. The frequency of heterozigous genotype AG was nine times higher in patients with endometriosis (59.3%) than in the control group (6.5%). The fertile patients (68%) had a frequency of AG 10.5 times higher than in the control group (6.5%) and infertile (55.6%) 8.5 times higher than in the control group. Social habits like smoking, alcohol, contraceptives and physical activity was not found a significant association. Of the patients with genotypes ArgPro/ProPro (51.5%) of the polimorphism of p53 gene the AG frequency was 8.6 times higher than in the control group (6%). We conclude that the AG frequency of the RsaI polymorphism of the gene REβ is associated with the presence of endometriosis.