Different distributions of VH CDR3 lengths in subgroups of MCL clones using different IGHV genes.IGHV3-21 (A), IGHV3-23 (B), IGHV1-8 (C), and IGHV4-34 (D) rearrangements against all other rearrangements. Skewing to longer VH CDR3s is observed among IGHV3-21 and IGHV4-34 rearrangements, contrasting IGHV3-23 and IGHV1-8 rearrangements that carry significantly shorter VH CDR3s.