It has been suggested that polymorphisms of the hBD-1-related gene (DEFB1) and ethnicity may cause these inconsistencies, as they may be connected to the diversity in the amounts of hBD-1 expression and severity of periodontitis that an individual develops.12 One of the hypotheses regarding various expression patterns of hBD-1 is that the expression does not decrease in periodontitis. The gene discussed is DEFB1; the disease is periodontitis.