Potential Role of Serotonin Transporter Gene (5-Htt) Polymorphism in Temporal Lobe Epilepsy Susceptibility in Egyptian Patients

摘要

Background: Serotonin (5-hydroxytryptamine, 5-HT) influences the cortical and subcortical excitatory/inhibitory balance and may participate in the pathophysiological processes of epilepsy. The serotonin transporter (5-HTT) is the most important factor in serotonin inactivation. Objective: To investigate the possible associations of the upstream promoter region polymorphism as well as the intron 2-VNTR polymorphism of the 5-HTT gene with temporal lobe epilepsy (TLE) susceptibility in Egyptian patients. Methods: A case-control candidate gene study evaluating the frequencies of 5HTTLPR biallelic and 5HTTVNTR allele variants in TLE patients and healthy subjects. Genotypes were grouped according to transcriptional efficiency. Results: TLE patients had a higher significant frequency of 12/12 homozygous repeat in 5-HTTVNTR polymorphism (p0.05) than in healthy control. We found significant lower age of epilepsy onset in LL genotype for 5-HTTLPR than SL genotype (p0.05), 12/12 genotype patients had a significant lower age of epilepsy onset than other genotypes for 5-HTTVNTR polymorphism (p0.05). Frequency of seizures was significantly higher in LL genotype for 5-HTTLPR than in SS genotype, while frequency of seizures in 12/12 genotype for 5-HTTLPR polymorphism was highly significant higher and significantly higher than in both 10/10 and 10/12 genotypes respectively. Frequency of polytherapy treatment with antiepileptics was significantly higher in LL genotype for 5-HTTLPR polymorphism than other genotypes and in 12/12 genotype for 5-HTTVNTR polymorphism than other genotypes. Conclusion: 5-HTT polymorphism is associated with increased susceptibility to temporal lobe epilepsy, it also associated with earlier age of onset of seizures, increased frequency of seizures and polytherapy treatment with antiepileptics. [Egypt J Neurol Psychiat Neurosurg.  2014; 51(1): 1-6]