In an attempt to discriminate between patients with mastocytosis with or without anaphylaxis, in addition to plasma tryptase, three new proteins were identified as candidate biomarkers, pregnancy-associated plasma protein-A (PAPP-A), galectin-3, and allergin-1, with significantly different levels in patients with mastocytosis with anaphylaxis compared with those without anaphylaxis [85]. This evidence concerns the gene MILR1 and mastocytosis.