In the myocardium of a patient with AA amyloidosis, six tryptic peptides of SAA were detected by LC-MS in samples containing both amyloid deposits and background tissue: two overlapping pairs of SAA peptides ([1–15 and 2–15] and [47–62 and 48–62]), as well as SAA 26–39 and SAA 68–87 peptides (Fig 1B). This evidence concerns the gene SAA1 and AA amyloidosis.