title: The +1858C/T PTPN22 gene polymorphism confers genetic susceptibility to rheumatoid arthritis in Mexican population from the Western Mexico.
abstract: BACKGROUND
  Rheumatoid arthritis (RA) is a common autoimmune disease with a complex genetic background. The PTPN22 gene encodes lymphoid tyrosine phosphatase LYP, a potent negative regulator of T cell activation. Polymorphic variants of this gene have previously been associated with various autoimmune disorders. The +1858C/T single-nucleotide polymorphism (SNP) (rs2476601), in the exon 14 of the PTPN22 gene has been associated with susceptibility to RA in several population.
  
  
  OBJECTIVE
  The aim of this work was to investigate whether the +1858C/T of the PTPN22 gene is associated with susceptibility to RA in Western Mexico population.
  
  
  METHODS
  A total of 309 unrelated RA patients, classified according to American College of Rheumatology (ACR) 1987 criteria, as well as 347 controls residents from Western Mexico were recruited for this study. The DNA samples were genotyped for +1858C/T PTPN22 gene SNP using the PCR-RFLP technique. Antibodies to cyclic citrullinated peptides (anti-CCP) were measured by enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  The frequency of +1858T risk allele was significantly increased in patients with RA compared with controls (p=0.001, OR=2.83, 95%CI=1.50-5.32). To confirm this results we established a comparison between subjects carrying of CT+TT genotypes versus those carrying CC genotype, between both groups (p=0.004, OR=2.65, 95%CI=1.33-5.36). Nevertheless, we not observed association of the +1858C/T PTPN22 gene SNP with clinical activity and functional disability in RA patients. Likewise, the +1858T variant in RA patients seropositive for anti-CCP antibodies, increased the risk for RA (p=0.008, OR=2.5, 95%CI=1.3-5.0) when we compared with controls; however, in the group of seronegative patients, no was found significant difference (p=0.1, OR=2.5, 95%CI=0.9-7.2).
  
  
  CONCLUSIONS
  Our results support the association of the +1858T risk allele of the +1858C/T PTPN22 polymorphism with susceptibility to RA and confirm that, in combination with anti-CCP antibodies, this SNP influence the autoimmune processes towards a development of RA in Mexican population.
authors: Doctorado en Ciencias Biomédicas, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
authors: Nora Magdalena
authors: NM
authors: Torres-Carrillo
authors: Yeniley
authors: Y
authors: Ruiz-Noa
authors: Gloria Esther
authors: GE
authors: Martínez-Bonilla
authors: Sergio Daniel
authors: SD
authors: Leyva-Torres
authors: Norma
authors: N
authors: Torres-Carrillo
authors: Claudia Azucena
authors: CA
authors: Palafox-Sánchez
authors: Rosa Elena
authors: RE
authors: Navarro-Hernández
authors: Héctor
authors: H
authors: Rangel-Villalobos
authors: Edith
authors: E
authors: Oregón-Romero
authors: José Francisco
authors: JF
authors: Muñoz-Valle
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000235:genetics*; D001323:Autoantibodies / Q000097:blood; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008800:Mexico; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D054596:Protein Tyrosine Phosphatase, Non-Receptor Type 22 / Q000235:genetics*; D055815:Young Adult
chemical_list: D001323:Autoantibodies; C516765:PTPN22 protein, human; D054596:Protein Tyrosine Phosphatase, Non-Receptor Type 22