Patients with FBDS alone almost exclusively had LGI1-IgG4 antibodies (P = 0.009, Mann-Whitney U-test) whereas, overall, patients with cognitive impairment showed higher proportions of LGI1-IgG1 antibodies (P = 0.03, Mann-Whitney U-test, Fig. 4C). The gene discussed is LGI1; the disease is Cognitive impairment.