TAC1 and pneumonia: Brown et al provided evidence that rs4340 genotypes induce cough by suppressing the tissue levels of bradykinin and substance P; the I/I and I/D genotypes had a higher cough reflex relative to the D/D genotype.35,36 D/D genotype was also reported to increase serum levels of the proinflammatory AT-II.37 It is known that reduced bradykinin and substance P levels repress cough reflex and therefore increase the risk to develop pneumonia.