Interleukin 1b Gene Promoter Polymorphism Is Associated with Temporal Lobe Epilepsy: A Systematic Review and Meta Analysis

KAUFFMAN MARCELO; GONZALEZ MORON DOLORES; CONSALVO DAMIAN; KOCHEN SILVIA

San Diego, EEUU

Congreso; 1st North American Regional Epilepsy Congress; 2006

AES

RATIONALE: Previous studies have examined the role of a single nucleotide polymorphism (SNP) at the promoter region of Interleukin 1b gene (IL1b -511T) on Temporal Lobe Epilepsy (TLE) and Febrile Seizures (FS) susceptibility, but they have been inconclusive. The aims of the present study were to define the role of this polymorphism on TLE and FS susceptibility and to obtain more precise estimates of the risk associated with this genetic variant., METHODS:Published studies up to Febuary 2006 of TLE, FS and IL1b -511T SNP were identified by searches of PubMed, Biosis, Web of Science and Embase databases. Meta-analysis of TLE and FS case-control data were performed to assess the association of IL1b -511T SNP with TLE, TLE with Hippocampal Sclerosis (TLEHS) and FS. Pooled Odds Ratios were estimated by means of a genetic-model free approach. Quality of Studies included was assessed by a score. Publication Bias was investigated by Egger and Begg tests., RESULTS:A total of 12 studies were included where 7 examined the association with TLE (with a total of 1798 subjects) and 5 examined the association with FS (with a total of 1299 subjects). The data analyzed by the genetic model-free approach indicated that the best model of inheritance is recessive. This model for allele T produced significant results in the TLE sample [fixed effects odds ratio 1.30 (1.01-1.69)] and in the TLEHS sample [fixed effects odds ratio 1.69 (1.26-2.27)] (Figure below), whereas for FS the results were non-significant [fixed effects odds ratio 1.33 (0.95-1.84)]. There was not evidence of Publication bias (Egger and Begg tests non-significant for TLE, TLEHS and FS samples). Quality was heterogeneous between studies., CONCLUSIONS:Overall, these findings support a role for IL1b -511T gene variant in TLE under a recessive mode of inheritance. Further explorations of the involvement of the IL1b gene in the susceptibility to FS, with a greater number of studies with larger sample sizes, are needed to fully establish the role of the IL1b gene in this condition.[