Two other studies showed significant differences only in the distribution of the DRB1*15 allele group (French West indies26—8.3%-NMO vs 24.8%-MS, pF = 0.015; India31—9.0%-NMO vs 21.0%-MS, pcF = 0.001). The gene discussed is HLA-DRB1; the disease is neuromyelitis optica.