Background:
Several studies have
examined
associations between
TNF-α polymorphisms
and asthma risk, but
the results have
been conflicting.
Methods: A
search was performed
of the PubMed,
EMBASE, and Wanfang
databases. Data were
extracted and pooled
ORs with 95% CIs
were calculated.
Results:
Fifty-four studies
were included. A
significant
association between
the TNFA -308A/G
polymorphism and
asthma
susceptibility was
observed for AA+AG
vs GG (OR, 1.39; 95%
CI, 1.23-1.58;
P<.001). This
polymorphism was
also significantly
associated with
asthma risk in
whites (OR, 1.47;
95% CI, 1.25-1.73;
P<.001), atopic
asthma risk (OR,
1.38; 95% CI,
1.16-1.65; P<.001),
pediatric asthma
risk (OR, 1.48; 95%
CI, 1.23-1.79;
P<.001), and adult
asthma risk (OR,
1.35; 95% CI,
1.21-1.52; P<.001).
There was also a
significant
association between
the TNFA -857C/T
polymorphism and
asthma risk in the
recessive model (OR,
1.25; 95% CI,
1.10-1.43; P<.001).
In the subgroup
analyses, asthma
risk was
significantly
increased in Asians
(OR, 1.23; 95% CI,
1.07-1.41; P=.004)
and atopic
individuals (OR,
1.33; 95% CI,
1.13-1.57; P<.001).
No significant
association was
found for the TNFA
-238A/G
polymorphism. There
were insufficient
data to evaluate
the associations
between TNFA
-1031T/C and -863C/A
polymorphisms and
asthma risk.
Conclusions:
This meta-analysis
suggests that TNFA
-308A/G and -857C/T
polymorphisms are
risk factors for
asthma.
Key words:
Asthma. Tumor
necrosis factor-α.
Meta-analysis.
Polymorphism. |