INTERNATIONAL ARCHIVES OF MEDICINE SECTION: LABORATORY MEDICINE ISSN: 1755-7682 1 2015 Vol. 8 No. 6 doi: 10.3823/1605 iMedPub Journals http://journals.imed.pub © Under License of Creative Commons Attribution 3.0 License This article is available at: www.intarchmed.com and www.medbrary.com Aberrant FOXP3 gene expression in eutopic and ectopic endometrium of infertile women with endometriosis ORIGINAL 1 Human Reproduction and Genetics Center - Faculdade de Medicina do ABC, Santo André/SP, Brazil. Contact information: Bianca Bianco. Faculdade de Medicina do ABC. Tel-Fax: (55) 1 4993-5464 Address: 4400 Avenida Príncipe de Gales, 821 – Santo André/SP, CEP 09060-650, Brasil.  bianca.bianco@hotmail.com Gustavo Mendonça Andre, Fernanda Abani Mafra, Viviane Cavalcanti, Tatiana Guida Ponce, Denise Maria Christofolini, Bianca Bianco, Caio Parente Barbosa Abstract Background: Immunological theories suggest that changes in the immune system could prevent the ability to eliminate the endome- trium of the pelvic cavity. In women with endometriosis is possible that changes in immunity mediated by T cells facilitate the implantation of endometrial fragments or cells in ectopic locations and recent studies have associated the FOXP3 gene with homeostasis of the immune system and the development of autoimmune diseases. We aimed to evaluate the expression of FOXP3 gene in both eutopic and ectopic endometrium of infertile women with endometriosis and controls. Methods: A case-control study was performed comprising 25 inferti- le women with endometriosis and 44 fertile women without endome- triosis. FOXP3 and GAPDH expression was measured by mRNA using quantitative reverse transcription polymerase chain reaction (qRT-PCR) based on TaqMan methodology. The Mann-Whitney test was used to compare the values between the groups. Results: The results disclosed that mean expression of FOXP3 in eutopic endometrium of endometriosis group was signifcantly higher when compared to the control group (p=0,008), regardless the stage of the disease. Considering the samples of the ectopic endometrium, FOXP3 expression was also signifcantly higher in endometriosis group compared to the control group (p=0,004), regardless the stage of the disease.