Similarly, ALS [OCB type 2/3 4.6%; IgG (Reiber) 0%; IgA (Reiber) 0%; IgM (Reiber) 0.8%] patients as well as controls [OCB type 2/3 0%; IgG/A/M (Reiber) 0%, P = 0.999; 0.999; 0.999; 0.999] and dementia [OCB type 2/3 2.5%; IgG (Reiber) 1.6%; IgA (Reiber) 0%; IgM (Reiber) 2.5%, P = 0.999; 0.999; 0.999; 0.999] patients rarely exhibited intrathecal IgG- and IgA synthesis, clearly differentiating them from PPMS patients [OCB type 2/3 77.3%; IgG (Reiber) 45.5%; IgA (Reiber) 4.5%; IgM (Reiber) 4.5%, P < 0.001; <0.001; 0.003; 0.999]. The gene discussed is CD79A; the disease is primary progressive multiple sclerosis.