High risk association of IL-4 VNTR polymorphism with asthma in a North Indian population.
BACKGROUND
A case-control study was conducted to evaluate the role of IL-4 VNTR polymorphism in asthma that has been associated with various inflammatory diseases worldwide. This is the first case-control study conducted in India, investigating the role of IL-4 VNTR polymorphism in asthma pathogenesis.


METHODS
A case-control study was performed with a total of 824 adult subjects, inducting 410 asthma patients and 414 healthy controls from North India. The genotypes were identified by polymerase chain reaction.


RESULTS
Statistical analysis for the IL-4 VNTR polymorphism revealed that the Rp1 allele was significantly associated with asthma with OR=1.47, 95% CI (1.11-1.94) and p=0.005. The Rp1/Rp1 homozygous mutant genotype posed a high risk towards asthma with OR=2.39, 95% CI (0.96-6.14) and p=0.040. The Rp2/Rp1 heterozygous genotype also posed a risk towards asthma with OR=1.39, 95% CI (1.00-1.94) and p=0.040. Most of the phenotypic traits were significantly associated with the disease.


CONCLUSIONS
IL-4 VNTR polymorphism is a high risk factor for asthma in the studied North Indian population.
Department of Biotechnology, Panjab University, Chandigarh, India. Electronic address: nitibirbian@yahoo.com.
Niti
N
Birbian
Department of Biotechnology, Panjab University, Chandigarh, India. Electronic address: jagtar72@gmail.com.
Jagtar
J
Singh
Department of Pulmonary Medicine, PGIMER, Chandigarh, India. Electronic address: skjindal@indiachest.org.
Surinder Kumar
SK
Jindal
Department of Biotechnology, Panjab University, Chandigarh, India. Electronic address: rcsobti@pu.ac.in.
Ranbir Chander
RC
Sobti
D000328:Adult; D001249:Asthma / Q000150:complications / Q000235:genetics*; D016022:Case-Control Studies; D002675:Child, Preschool; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D007194:India; D015847:Interleukin-4 / Q000235:genetics*; D008297:Male; D018598:Minisatellite Repeats / Q000235:genetics*; D010641:Phenotype; D011014:Pneumonia / Q000150:complications / Q000235:genetics; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012307:Risk Factors
C508598:IL4 protein, human; D015847:Interleukin-4
Asthma; IL-4 VNTR polymorphism; North Indian population; Risk