Significant differences in the prevalence and risk of bronchitis were found in genotypes of LT-α and TNF-α, but not in ALOX5, LTC4S, TBXA2R, ADAM33, NOS1 and ORMDL3 in the Inuit populations residing both in Greenland and in Denmark (Supplementary Table S4). Here, ORMDL3 is linked to bronchitis.