Association between the M129V variant allele of PRNP gene andmild temporal lobe epilepsy in women

Specific variations in the prion protein gene (PRNP) are associated with, and prevalent in patients with intractable temporal lobe epilepsy (TLE) and influence the surgical outcome. We investigated whether or not the PRNP gene is a susceptibility gene in temporal lobe epileptic patients with mild epilepsy. We systematically screened the entire open reading frame of the PRNP gene and evaluated the genetic contribution of the functional PRNP M129V polymorphism in 289 patients with mild TLE compared with a neurologically unaffected age and sex matched control group (n = 272). Statistical analysis revealed a moderate difference in the distribution at codon 129 of the PRNP gene between sporadic mild TLE patients and healthy controls (p = 0.036; OR= 1.30; 95% CI = 1.01–1.68). Although, there was no statistically significant difference in the genotype distribution within the study groups (p = 0.101), a further analysis showed that the 129V allele was highly represented only in women with TLE compared with control group (p = 0.006, OR= 1.632; 95%CI = 1.15–2.31). This is the first publication of data that support the hypothesis that the common methionine/valine polymorphism at codon 129 of the PRNP gene may modify the susceptibility of women to mild TLE.