ADAMTS13 synonymous variant characteristics. (A) Schematic diagram of ADAMTS13 exons and encoded protein domains with the number of sSNVs in each exon and domain (in italic red). (B) Proportion of 376 variants present in first codon position (solid red) or in third codon position (red outline). Proportion of sSNVs found in patients with USS (yellow). Proportion of variants present in each exon, normalized by exon length (gray). (C) Distribution of 12 possible nucleotide substitutions of synonymous mutations across ADAMTS13 exons and the percentage of variants with given nucleotide substitution provided in parentheses.