Fig. 4. Inter-lineage structure of IgGs in visit 2 PBMCs.

Inter-lineage structure of IgGs in visit 2 PBMCs is presented for six randomly selected subjects (A-B, age 8-17; C-D, age 18-32; E-F, age 70-100). Each dot represents a lineage of antibody sequences defined by single linkage clustering with 1 amino acid difference at CDR3 as the threshold. The area of the dot is proportional to the number of reads belonging to this lineage, as indicated in the scale bar. X-axis is the diversity of the lineage which measures number of unique protein sequences (full protein sequence, not just the CDR3 region) within the lineage. Y-axis is the number of mutations at nucleotide level of the lineage averaged over reads. 3000 reads of subsampling was applied.