Using summary data from genome‐wide association studies on serum 25‐hydroxyvitamin D [25(OH)D] levels (N = 417,580), VDBP concentrations (N = 65,589), and various types of epilepsy (Ncases = 27,559), MR analyses were conducted to determine bidirectional causal relationships among these variables. The gene discussed is GC; the disease is epilepsy.