The most significant signal from this analysis of combined NMO (rs28383224, MAF = 0.42, OR = 2.24, P = 5.8 × 10−12) mapped 21.5 kb downstream of HLA-DQA1 (Table 1, Supplementary Fig. 4, Supplementary Table 9, Fig. 2a). The gene discussed is HLA-DQA1; the disease is neuromyelitis optica.