title: Dopamine receptor D2 genotype (3438) is associated with moderate/severe endometriosis in infertile women in Brazil.
abstract: OBJECTIVE
  To compare the prevalence of dopamine receptor D2 polymorphisms in patients with peritoneal endometriosis and in healthy control subjects.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  One hundred seven women aged ≥18 years who were enrolled when seeking care for infertility caused by peritoneal endometriosis or for tubal ligation.
  
  
  METHODS
  We performed DNA extraction of peripheral blood, followed by polymerase chain reaction to confirm single-strand polymorphisms and to sequence two polymorphisms.
  
  
  METHODS
  We sequenced two polymorphisms in exon 7 of the dopamine receptor D2 (DRD2) gene. Polymorphism 1 occurs in nucleotide 3420 (cytosine to thymine, 313 histidine), and polymorphism 2 occurs in nucleotide 3438 (cytosine to thymine, 319 proline).
  
  
  RESULTS
  The frequency of the DRD2 polymorphism 2 was increased in subjects with peritoneal moderate/severe endometriosis. Analysis of the DRD2 genotypes demonstrates an odds ratio of 2.98 (95% confidence interval 1.47-6.04) for polymorphism 2 in peritoneal moderate/severe endometriosis.
  
  
  CONCLUSIONS
  Our results revealed that an excess of DRD2 polymorphism 2 was found in exon 7 in women with peritoneal moderate/severe endometriosis. The presence of polymorphism 2 could cause a defect in a post-receptor signaling mechanism, resulting in a mild increase in serum prolactin levels. Thus, the potential angiogenic role of prolactin may play a role in the implantation of ectopic endometriosis tissue.
authors.affiliation: Department of Obstetrics and Gynecology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil. joaopaolobilibio@yahoo.com.br
authors.forename: João Paolo
authors.initials: JP
authors.lastname: Bilibio
authors.forename: Ursula
authors.initials: U
authors.lastname: Matte
authors.forename: Emily
authors.initials: E
authors.lastname: de Conto
authors.forename: Vanessa Krebs
authors.initials: VK
authors.lastname: Genro
authors.forename: Carlos Augusto
authors.initials: CA
authors.lastname: Souza
authors.forename: João Sabino
authors.initials: JS
authors.lastname: Cunha-Filho
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil; D016022:Case-Control Studies; D004715:Endometriosis / Q000235:genetics* / Q000378:metabolism; D005091:Exons / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D007247:Infertility, Female / Q000235:genetics* / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011388:Prolactin / Q000097:blood; D017448:Receptors, Dopamine D2 / Q000235:genetics* / Q000378:metabolism; D012720:Severity of Illness Index; D015398:Signal Transduction / Q000502:physiology; D013246:Sterilization, Tubal; D055815:Young Adult
chemical_list: D017448:Receptors, Dopamine D2; D011388:Prolactin