Deduced amino acid sequences of immunocytoma V_H genes. The amino acid sequences of the most homologous germline V_H genes are shown above the lymphoma sequences. Dashes indicate sequence identity. Amino acid replacement mutations are shown as upper case letters. The location of silent mutations in the nucleotide sequence is indicated with lower case letters. PB, BM, and LN indicate the tissue from which the lymphoma V_H sequence was obtained. Sequences labeled with an asterisk were obtained from an independent set of RT/PCR, cloning, and sequencing reactions. The IgG V_H sequences from SEL are labeled gSEL.