For instance, the highest-ranked antibody, R01736, a DNA-Ab, showed outstanding staining of colon carcinoma and colonic epithelium, moderate staining of sweat ducts (known to express CEA [4]) and neutrophils, but showed no staining of other normal tissues known not to express CEA, such as skin (dermis and epidermis), prostate glands and stroma, colon muscularis propria, and skeletal muscle tissues (Figure 5). The gene discussed is CEACAM5; the disease is colon carcinoma.