Average numbers of amino acid differences in the CDR sequences from the closest human germline CDR sequence.

a CDR-H3 was not analyzed because there were no germline sequences to compare with.b Designed CDR sequences as described in the text.c The library CDR sequences that did not match any of the designed sequences but had the correct length.d Natural human CDR sequences with corresponding length retrieved from the IMGT database.Average numbers of amino acid differences in the CDR sequences from the closest human germline CDR sequence.