Interestingly, several antimicrobial proteins differentially expressed in nasal mucosa from patients with chronic rhinosinusitis (e.g. BPIFA1, BPIFB1, BPIFB2, LTF, LYZ, S100A8, S100A9)46 were upregulated in amniotic fluid with increasing gestational age. The gene discussed is BPIFB1; the disease is chronic rhinosinusitis.