A NOS1 gene polymorphism associated with asthma and specific immunoglobulin E response to mite allergens in a Colombian population.
BACKGROUND
Nitric oxide (NO) is involved in asthma pathogenesis and is synthesized by three isoforms of NO synthase, one of them encoded by NOS1 gene. The CA-repeat and the C5266T SNP in NOS1 exon 29 have been associated with asthma and IgE levels. We thought to test the association of asthma and asthma-related phenotypes with the exon 29 CA-repeat and the C5266T SNP in a Colombian population sample.


METHODS
The CA-repeat and the C5266T SNP were genotyped in 167 asthmatics and 166 controls using PCR-based fragment length polymorphism and TaqMan assay. We also determined total and mite-specific IgE against Blomia tropicalis and Dermatophagoides pteronyssinus.


RESULTS
Three new CA-repeat alleles, 14, 23 and 24 repeats were detected. Allele comprising 16 repeats was associated with asthma (OR: 1.90 (CI 1.22-2.97, p(c) = 0.028) and low total (p(c) = 0.02) and specific IgE to B. tropicalis (p(c) < 0.0001) and D. pteronyssinus (p(c) < 0.0001). We found no association of the C5266T SNP and asthma or IgE levels.


CONCLUSIONS
NOS1 exon 29 CA-repeat may be a risk factor for asthma susceptibility and mite specific IgE response in a Colombian population.
Martínez
B
B
Institute for Immunological Research, University of Cartagena, Cartagena, Colombia.
Barrios
K
K
Vergara
C
C
Mercado
D
D
Jiménez
S
S
Gusmão
L
L
Caraballo
L
L
D000053:Acari; D000328:Adult; D000483:Alleles; D000485:Allergens / Q000276:immunology*; D000818:Animals; D001249:Asthma / Q000235:genetics* / Q000276:immunology; D003105:Colombia; D040002:Dermatophagoides pteronyssinus; D018900:Dinucleotide Repeats / Q000235:genetics; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology*; D008297:Male; D052248:Nitric Oxide Synthase Type I / Q000235:genetics*; D011110:Polymorphism, Genetic
D000485:Allergens; D007073:Immunoglobulin E; C496320:NOS1 protein, human; D052248:Nitric Oxide Synthase Type I