Intraclonal Ig sequence variations in case 1. Identity with the germline sequence is shown by dashes, replacement mutations are shown by uppercase letters, and silent mutations are shown by lowercase letters. Sequence variations are highlighted in bold. The primer sequences are not included. F, follicular neoplastic B cells; IF, interfollicular neoplastic B cells. s prefix indicates clones analyzed from a separate tissue block; and * indicates nucleotide deletions.