As shown in Table 2, after the mass spectrometry analysis, we identified 15 main spots, three of which (M, N, and S), corresponding to the Fc fragment of IgG binding protein (Fcgbp), transthyretin (TTR), and proproteinase E, respectively, were present in the feces of dogs with lymphangiectasia but not in healthy dogs [23]. The gene discussed is TTR; the disease is lymphangiectasis.