Some rural populations in Brazil chronically exposed to insect bites, such as blackflies and reduviid (vector of Chagas disease) exhibit an autoantibody response against Dsg1 (Diaz et al., 2004).Interestingly, approximately 50% of the normal population possess nonpathogenic anti-Dsg1 autoantibodies (Warren et al., 2000; Qaqish et al., 2009). The gene discussed is DSG1; the disease is Chagas disease.