title: T-cell receptor beta polymorphism is not associated with endometriosis.
abstract: OBJECTIVE
  We carried out an association study between T-cell receptor beta polymorphism (TCRB) and endometriosis to investigate the difference in allelic frequency. Polymorphisms in T-cell receptor genes can provide important information for the study of the immune response and autoimmune diseases; indeed, rs1800907, a very common single nucleotide polymorphism (SNP) of the TCRB, has been extensively studied in autoimmune diseases in the 1990s using Southern blot analysis and more recently polymerase chain reaction (PCR) and sequencing. An autoimmune etiology for endometriosis has been strongly suggested for the presence of antibodies against endometrium, high rates of autoimmune disorders and associated atopic diseases.
  
  
  METHODS
  We investigated 70 patients with endometriosis and 120 controls. DNA of patients and controls was studied by PCR followed by restriction digestion and sequencing to determine genotype and presence of linkage disequilibrium (LD). Statistical analysis was carried out using STATA Routine GENHW (StataCorp, College Station, TX, USA) for estimation of Hardy-Weinberg equilibrium and test power calculation. The difference of allele distribution between patients and controls was calculated according to Pearson's and Fisher's tests. Test power for the estimation of linkage disequilibrium is low (0.16).
  
  
  RESULTS
  We performed an association study of the SNP rs1800907 of TCRB between 70 patients with endometriosis and 120 controls, and did not find any significant difference (χ(2) = 0.27 and P = 0.87). Fisher's test confirmed a P-value of 0.872.
  
  
  CONCLUSIONS
  Our study does not suggest an evidential and major involvement of TCRB in the pathogenesis of endometriosis in an Italian population in a small case control study.
authors: Departments of Medicine, Surgery and Dentistry, San Giuseppe Hospital, Milan, Italy. pasquale.tripputi@unimi.it
authors: Pasquale
authors: P
authors: Tripputi
authors: Monica
authors: M
authors: Bignotto
authors: Daniela
authors: D
authors: Cigognini
authors: Stefano
authors: S
authors: Bianchi
authors: Luigi
authors: L
authors: Fedele