Apolipoprotein E Polymorphisms and the Risk of Nonlesional Temporal Lobe Epilepsy

Purpose: To evaluate whether the inheritance of the apolipoprotein E (ApoE) ε4 allele is a risk factor for nonlesional temporal lobe epilepsy (TLE), and to determine whether the newly described ‐491 A/T ApoE polymorphism may independently affect the risk of nonlesional TLE. Methods: The study group consisted of 63 patients (35 women and 28 men; age at onset of epilepsy, 30.6 ± 19.6 years; mean (±SD). All of them had received a diagnosis of nonlesional TLE after a detailed clinical, electroencephalographic, and brain magnetic resonance investigation. The ApoE polymorphisms were determined from blood samples by standard methods. The molecular study also was performed in 220 age‐ and sex‐matched normal individuals. Results: There were no differences between TLE patients and controls in either allelic or genotypic frequencies of the ApoE and ‐491 A/T polymorphisms. Moreover, no effect of ApoE or ‐491 A/T polymorphisms was found on the age at onset and severity of epilepsy. Conclusions: The allelic and genotypic frequencies of ApoE polymorphisms in Italian patients with nonlesional TLE are comparable to control values, indicating that ApoE polymorphisms are not a significant genetic risk factor for the occurrence of nonlesional TLE.