Association of IL-6 gene polymorphisms and COPD in a Spanish population.
Interleukin-6 (IL-6) is a potential mediator of systemic effects of Chronic Obstructive Pulmonary Disease (COPD). In the present case-control study we investigated the association of promoter polymorphisms of this gene and COPD in a cohort of 191 patients, smokers without COPD (n=75) and a healthy control population (n=296). Besides spirometry, exercise capacity (6MWD, 6 min walking distance) and body mass index (BMI) were measured in COPD patients. Genotyping of the IL-6 polymorphisms at positions -174, -572 and -597 was performed. The -597G/A and -174G/C polymorphisms were not associated with the disease. However, the -572G/C polymorphism was significantly associated with COPD susceptibility under a dominant model of inheritance. The frequency of the genotypes containing the C allele was significantly lower in the COPD cases (9.9%) compared with the healthy control group (16.9%) and smokers (23.1%), (OR=0.46, p=0.032 and OR=0.28, p=0.012, respectively). The GCG (-597/-572/-174) haplotype was significantly associated with the disease (OR=0.37, p=0.022, COPD cases vs. healthy subjects and OR=0.17, p=0.011, COPD cases vs. smokers). Moreover, a borderline association was also found for the -572G allele and hypoxemia (PaO(2)<60 mmHg) (p=0.05). Our data suggest that the IL-6 -572C allele may confer a diminished risk of developing COPD.
Córdoba-Lanús
Elizabeth
E
Research Unit, Hospital Universitario Nuestra Señora de Candelaria, Ctra. del Rosario s/n, Santa Cruz de Tenerife 38010, Spain. elizabeth-cordoba@hotmail.com
de-Torres
Juan-Pablo
JP
López-Aguilar
Celeste
C
Rodríguez-Pérez
María-Cristo
MC
Maca-Meyer
Nicole
N
Montejo-de-Garcini
Angela
A
Aguirre-Jaime
Armando
A
Pérez-Méndez
Lina
L
Casanova
Ciro
C
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D005260:Female; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic / Q000235:genetics; D029424:Pulmonary Disease, Chronic Obstructive / Q000235:genetics*; D012907:Smoking / Q000235:genetics
D005819:Genetic Markers; D015850:Interleukin-6