IGHM and Schnyder corneal dystrophy: Additional sub‐clustering of B cells identified a population of naïve B cells (Figure 3C, cluster 1), expressing IGHD and IGHM; a cluster expressing genes consistent with a memory B cell phenotype (Figure 3C, cluster 2); and a small subset of B cells expressing germinal centre markers including BCL6 and AICDA (Figure 3C, cluster 3), the latter of which were almost exclusively found in SCD but not NSCD.