The haplotype “TA” of the SFTPB (rs1130866 x rs7316) exhibited an additive effect, OR = 0.17 (0.05–0.64), whereas, the haplotype “TA” of the SFTPD (rs721917 x rs2243639) exhibited a dominant effect, OR = 0.35 (0.18–0.66) on decreasing the risk of HP. The gene discussed is SFTPD; the disease is hypersensitivity pneumonitis.