Besides, pathways associated with cancer and apoptosis were also significantly affected, eg hereditary breast cancer signalling, IL‐6 signalling, GADD45 signalling.29, 30 Other altered pathways include hepatic fibrosis/hepatic stellate cell activation, aryl hydrocarbon receptor signalling, glucocorticoid receptor signalling, pyridoxal 5′‐phosphate salvage pathway, airway pathology in chronic obstructive pulmonary disease and osteoarthritis pathway, which suggest the abnormalities in disease states and functions, eg biosynthesis.31 The gene discussed is AHR; the disease is chronic obstructive pulmonary disease.