CD79A and Charcot-Marie-Tooth disease type 3: Comparison of the proportion of isotypes by group (Fig. 1A) showed that the proportion of BCR with unswitched isotypes (IgM and IgD) was greater and the proportion of switched isotypes (IgG and IgA) was lower in the patients from the HC group than in those from disease groups (NMOSD, MOGAD, and DSN).