Mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) is one of the most common medically intractable epilepsy syndromes and the pathogenesis of HS remains highly obscure. Recent studies demonstrated controversial results about the relationship between interleukin (IL) gene polymorphism and epilepsy in different ethnic groups. This correlation was investigated in Turkish patients with MTLE-HS. The allele distribution of IL-1 alpha and IL-1 beta in 47 patients of Turkish ancestry was determined and compared with 99 ethnically matched control subjects. Analysis of genotype frequencies between patients and controls showed no statistically significant difference (p > 0.05). Our data suggest that IL-1 alpha and IL-1 beta gene polymorphisms do not act as a strong susceptibility factor for MTLE-HS in individuals of Turkish ancestry. (C) 2006 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.