The final population PK-PD model for the probability of the γ-GT elevation was as follows:(9)where AUC is the individual AUC value of VPA that was simulated based on the population PK analysis; intellectual disability = 1 if an intellectual disability was present, and was otherwise 0; SOD2 Val/Val genotype = 1, SOD2 Val/Ala or Ala/Ala genotype = 0; and η is the individual random effect. This evidence concerns the gene SOD2 and Intellectual disability.