Helmstaedter et al. conducted multiple SNP analyses of genes related to dopaminergic activity in 398 patients with epilepsy and taking LEV.[32] They revealed a higher load of adverse psychotropic side effects of LEV in patients carrying rs1800497 (dopamine receptor D2-associated ANKK1 TAQ-1A), which is associated with decreased dopaminergic activity. This evidence concerns the gene ANKK1 and epilepsy.