Interleukin-6 -174 G/C promoter polymorphism and nasal polyposis.
BACKGROUND
Nasal polyposis is a chronic disease with unknown etiopathogenesis, although inflammatory mechanisms seem to play a role. One of several inflammatory mediators linked to nasal polyposis is Interleukin-6, which has a single nucleotide polymorphism -174 G/C that seems to promote an inflammatory reaction.


OBJECTIVE
To compare the prevalence of the -174 G/C single nucleotide polymorphism between a group of patients with nasal polyposis and a control group.


METHODS
Cross-sectional study with two groups (thirty two patients with nasal polyposis and fifty five controls) to investigate the -174 G/C polymorphism in blood samples. Asthma, aspirin intolerance and atopy were main exclusion criteria. IL-6 genotyping was performed using the PCR method with forward primer 5'-ATGCCAAGTGCTGAGTCACTA-3' and reverse primer 5'-GGAAAATCCCACATTTGATA-3', amplifying a 226-bp DNA fragment that contained the - 174 position. The amplified fragment can be cleaved by restriction enzyme NlaIII when the -174 position presented the C allele in two fragments of 117 and 109-bp, visualized by electrophoresis, classifying participants in GG, GC and CC.


RESULTS
In the nasal polyposis group, 65.62% of the patients had the GG genotype, while in the control group, 41.82% had two G alleles, a statistically significant difference, with an odds ratio of 2.65.


CONCLUSIONS
The -174 GG genotype was found more frequently in nasal polyposis patients than in controls, when asthma, aspirin intolerance and atopy were excluded.
Kosugi
Eduardo Macoto
EM
Department of Otorhinolaryngology and Head and Neck Surgery of São Paulo Federal University (UNIFESP-EPM), São Paulo, SP, Brazil. edumacoto@uol.com.br
de Camargo-Kosugi
Cínta Meirelles
CM
Weckx
Luc Louis Maurice
LL
Guerreiro-da-Silva
Ismael Dale Cotrim
ID
Gregorio
Luiz Carlos
LC
D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D053938:DNA Fragmentation; D004587:Electrophoresis, Agar Gel; D005260:Female; D005838:Genotype; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009298:Nasal Polyps / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*
D015850:Interleukin-6