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 bronchial disorder.