SCN1A rs3812718 polymorphism and susceptibility to epilepsy with febrile seizures: a meta-analysis.
BACKGROUND
Evidence showed that the SCN1A IVS5N+5G>A polymorphism might be associated with susceptibility to epilepsy with febrile seizures (EFS), however, the published data were inconclusive. Therefore, a meta-analysis was performed to estimate the overall EFS risk with the polymorphism.


METHODS
The PubMed and Medline were searched up to March, 2013 for studies on the association between SCN1A IVS5N+5G>A polymorphism and EFS risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by means of a genetic model free approach. The heterogeneity and sensitivity of each report and the publication bias were also performed. All the statistical analyses were done using the STATA 11.0 software.


RESULTS
A total of 6 studies with 2719 cases and 2317 controls met the selection criteria. We found significant association between SCN1A polymorphism and EFS (A vs. G: OR=1.498, 95%CI=1.138-1.972; AA vs. GG: OR=2.292, 95%CI=1.620-3.243; AG vs. GG: OR=1.414, 95%CI=1.010-1.978; recessive model: OR=1.747, 95%CI=1.119-2.728 and dominant model: OR=1.730, 95%CI=1.259-2.376). When compared with the epilepsy without febrile seizure (EWFS), the subgroup analysis stratified by ethnicity showed that the SNP was significantly associated with EFS in Caucasian (A vs. G: OR=1.505, 95%CI=1.218-1.861; AA vs. GG: OR=2.081, 95%CI=1.358-3.189; recessive model: OR=1.715, 95%CI=1.273-2.310 and dominant model: OR=1.625, 95%CI=1.096-2.410), but not in Indian and Chinese. When applying Bonferroni correction (significance was set at 0.05/20), the Caucasian still has robust association with EFS and epilepsy.


CONCLUSIONS
The present meta-analysis suggests that SCN1A IVS5N+5G>A polymorphism is a risk factor of EFS and epilepsy, especially in Caucasian.
Department of Neurosurgery, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu 210029, China.
Linjun
L
Tang
Xiaocheng
X
Lu
Yi
Y
Tao
Jinyu
J
Zheng
Penglai
P
Zhao
Kai
K
Li
Lixin
L
Li
D004827:Epilepsy / Q000235:genetics*; D018740:Genetic Heterogeneity; D020022:Genetic Predisposition to Disease; D006801:Humans; D062550:NAV1.1 Voltage-Gated Sodium Channel / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D003294:Seizures, Febrile / Q000235:genetics*
D062550:NAV1.1 Voltage-Gated Sodium Channel; C568242:SCN1A protein, human
95% CI; 95% confidence interval; EFS; Epilepsy; Febrile seizures; Gene; HWE; Hardy–Weinberg equilibrium; Meta-analysis; OR; Polymorphism; SCN1A; SNP; epilepsy with febrile seizure; odds ratio; single nucleotide polymorphism