Amino acid sequence alignment of IgH CDR3. The IgH CDR3 of SMZL cases using the VH1-02 gene from the current study are compared with those of published series of SMZL and CLL with VH1-02 usage.^21,22,33-35  The bottom 3 sequences are published VH1-69 IgH CDR3 sequences from marginal zone lymphomas in patients with hepatitis C virus infection. The alignment shows that the majority of SMZL cases that use the VH1-02 have considerably longer IgH CDR3 segments than CLL cases that use this gene. Of interest, SMZLs that use VH1-69 in patients with hepatitis C virus infections show different, short, and stereotyped sequences. Amino acids are color-coded as follows: gray for nonpolar, dark blue for uncharged polar, light blue for basic, and red for acidic amino acids.