title: Analysis of the rs20541 (R130Q) polymorphism in the IL-13 gene in patients with elderly-associated chronic inflammatory diseases.
abstract: OBJECTIVE
  To investigate whether there is association between the rs20541 (R130Q) polymorphism in the IL-13 gene with disease susceptibility and clinical subsets in patients with elderly-associated inflammatory chronic diseases.
  
  
  METHODS
  78 patients with giant cell arteritis (GCA), 174 with polymyalgia rheumatica (PMR), 90 elderly-onset rheumatoid arthritis (EORA), and 465 healthy controls from the same geographic area were studied. The rs20541 (R130Q) polymorphism in the IL-13 gene was evaluated by PCR-RFLP. Circulating levels of IL-13 were measured by ELISA.
  
  
  RESULTS
  A higher frequency of the AA genotype [2.349 (0.994-5.554)], as well as the allele A [1.589 (1.085-2.328] and the A carriers [1.656 (1.021-2.686)] (p<0.05) was observed in the GCA patients. No significant differences were observed in the PMR and EORA patients as compared with the healthy controls. Neither difference was observed among the different disease groups studied. In GCA patients, differences in the genotype were associated with a worse prognosis. In PMR patients, the AA genotype was associated with higher levels of serum IL-13 than the GA one. However, such an association was not detected for controls and the other disease groups.
  
  
  CONCLUSIONS
  GCA is more frequent in carriers of the rs20541 (R130Q) polymorphism in the IL-13 gene. The utility of this polymorphism to predict the GCA prognosis must be confirmed in studies with a higher number of patients.
authors: Servicio de Reumatología, Hospital Universitario Marqués de Valdecilla-IFIMAV, Facultad de Medicina, Universidad de Cantabria, Santander, España.
authors: Lorena
authors: L
authors: Alvarez-Rodríguez
authors: Marcos
authors: M
authors: López-Hoyos
authors: Eugenio
authors: E
authors: Carrasco-Marín
authors: Cristina
authors: C
authors: Mata
authors: Jaime
authors: J
authors: Calvo-Alén
authors: Elena
authors: E
authors: Aurrecoechea
authors: Ricardo
authors: R
authors: Blanco
authors: Teresa
authors: T
authors: Ruiz
authors: Pedro
authors: P
authors: Muñoz Cacho
authors: Ignacio
authors: I
authors: Villa
authors: Víctor Manuel
authors: VM
authors: Martínez-Taboada
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000235:genetics*; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D060005:Genotyping Techniques; D013700:Giant Cell Arteritis / Q000097:blood / Q000235:genetics*; D006801:Humans; D018793:Interleukin-13 / Q000097:blood / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011111:Polymyalgia Rheumatica / Q000097:blood / Q000235:genetics*
chemical_list: D015415:Biomarkers; D005819:Genetic Markers; C578095:IL13 protein, human; D018793:Interleukin-13