By comparison to VGKC-complex antibody determination, the detection of LGI1 or CASPR2-reactivity offers very good specificity for an antibody-mediated neurological syndrome, whereas low-titre VGKC-complex antibodies (between 100 and 400 pM) were noted in an elderly stroke cohort at a frequency of around 6%, rates of LGI1- and CASPR2-antibodies are much lower in controls [7], [14], [15], [16], [17], [18]. The gene discussed is CNTNAP2; the disease is Stroke.