SERPINA1 and pulmonary emphysema: ‘Patient A is a life‐long smoker. He grew up on a farm and all his family smoked. He has end stage emphysema and requires a lung transplant to survive. He is currently smoking. He is 45 and in otherwise good health. Patient B is a non‐smoker, but has end stage emphysema from alpha 1 antitrypsin deficiency. He is 40 but in poor health and had coronary artery bypass grafts last year. You can refer only one patient for lung transplantation next week. Who do you refer?’