IL-4 Gene Polymorphisms and Their Association With Atopic Asthma and Allergic Rhinitis in Pakistani Patients

RESUMEN

Introducción y objetivo: La IL-4 es una citocina que media las reacciones alérgicas. Diferentes polimorfismos en nucleótidos simples (SNPs) pueden influir sobre la respuesta mediada por citocinas. El motivo de este trabajo fue investigar la posible asociación de polimorfismos de la IL-4 con rinitis alérgica (RA) o asma atópica. Método: Se incluyó un total de 214 pacientes atópicos (asma n=108, RA n=106) y 120 controles sanos de Paquistán que fueron genotipados para SNPs IL-4 C-589T (rs2243250), T+2979G (rs2227284) y C-33T (rs2070874) mediante PCR. El análisis estadístico se llevó a cabo mediante el paquete StatCalc, EpiInfo v.6. Resultados: Observamos que el SNPs rs2243250 se asocia de forma significativa a asma (p 0.004; X2=11.0) y a RA (p<0.001; X2=20.2). Los genotipos más frecuentes en asma y RA fueron TT para SNP rs2243250, y GG para SNP rs2227284. Por otra parte, el SNP rs2070874 no se asocia con ninguna enfermedad respiratoria en una cohorte pakistaní. Conclusiones: rs2243250 y rs2227284 se asocian significativamente a asma y a RA. Los resultados de este estudio demuestran que además de los factores ambientales, los factores genéticos de riesgo juegan un papel importante en el desarrollo de las enfermedades atópicas respiratorias (AU)

ABSTRACT

Background and Objective: Interleukin (IL) 4 is a cytokine that mediates allergic responses. Different single nucleotide polymorphisms (SNPs) can influence the immune response mediated by cytokines. The aim of the present study was to investigate the possible association between IL-4 polymorphisms and allergic rhinitis and atopic asthma. Methods: A total of 214 atopic patients (108 with asthma and 106 with allergic rhinitis) and 120 healthy controls from Pakistan were genotyped for IL-4 SNPs C-589T (rs2243250), T+2979G (rs2227284), and C-33T (rs2070874) using restriction fragment length polymorphism-polymerase chain reaction. Statistical analysis was performed using the statistical software package StatCalc, EpiInfo v.6. Results: The SNP rs2243250 was significantly associated with both asthma (P=.004, X2=11.0) and allergic rhinitis (P<.001, X2=20.2), as was T-2979G (P<.001, 􀆵2=22.51 for asthma and P<.001, 􀆵2=57.6 for allergic rhinitis). The most frequent genotypes in the asthma and allergic rhinitis groups were TT for SNP rs2243250, and GG for SNP rs2227284. rs2070874 was not found to be associated with either of the 2 atopic respiratory diseases analyzed in the Pakistani cohort. Conclusions: rs2243250 and rs2227284 are significantly associated with asthma and allergic rhinitis. The results of this study indicate that in addition to environmental factors, genetic risk factors also play an important role in the development of atopic respiratory diseases (AU)