The mutation characteristics of FR3.

<p>(a) The overall mutation rates of FR3 in IGH, IGK, and IGL repertoires. NT represents the nucleotide and AA represents the amino acid. (b) The average mutation rates of FR3 among different functional V genes in IGH repertoire. (c-d) The distribution of mutation frequencies at each position of FR3 among functional V genes in IGH repertoire, at amino acid level (c) and nucleotide level (d). The grey rectangle indicates that no nucleotide was sequenced at that position or the number of nucleotide was less than or equal to 30 at that position.