HCDR3 amino acid sequence of stereotyped IGHV3-7 gene rearrangements. The 11 aa composing HCDR3 of each stereotyped IGHV3-7 case are aligned. The color reflects their origin: black, IGHV or IGHJ genes; blue, IGHD genes; red, N (or P) nucleotides; green, conserved anchor residues bordering HCDR3. Underlined amino acids resulted from replacement somatic mutations. Identical N-D-N residues for all cases in boxes. The IGHD genes contributing to HCDR3 are indicated on the right.