Distinct features of CLL epitypes revealed in combined analysis including all cohorts. (A) Epitype-specific distribution of IGHV mutations across 1095 patients (P < .0001). (B) Frequency of VH gene usage within epitype among the 16 most represented VH genes across all cohorts. (C) Frequency of immunoglobulin light chain usage within epitypes showing distinct usage of IGLV in IP-CLL (P < .0001). (D) Frequency of specific immunoglobulin light chain usage within epitypes among the 11 most frequent rearrangements. (E) Frequency of cytogenetic abnormalities by FISH within epitypes. (F) Frequency of most common recurrently mutated genes in CLL within epitypes. *P < .05, **P < .001, ***P < .0001, χ² test with Bonferroni correction.