A genome-wide discovery study for variants associated with lung function measures was performed in 48,943 individuals from the UK BiLEVE16 (link) subset of UK Biobank (UK BiLEVE, stage 1). In brief, UK Biobank comprised 502,682 individuals of whom 275,939 were of self-reported European-ancestry and had ≥2 Forced Expired Volume in 1s (FEV1) and Forced Vital Capacity (FVC) measures (Vitalograph Pneumotrac 6800, Buckingham, UK) passing ATS/ERS criteria46 (link). Based on the best (highest) available FEV1 measurement, 50,008 individuals from groups with extreme low (n=10,002), near-average (n=10,000) and extreme high (n=5,002) % predicted FEV1 were selected from amongst never-smokers (total n=105,272) and the same numbers from amongst the heavy-smokers (mean 35 pack-years of smoking, total n=46,758). FEV1, FVC and FEV1/FVC distributions are summarised in Supplementary Figure 8. Genotyping was undertaken using the Affymetrix Axiom UK BiLEVE array16 (link) and imputed to the 1000 Genomes Project Phase 147 (link) and UK10K48 ,49 (link) combined panel. A total of 27,624,732 imputed or directly genotyped autosomal variants with imputation quality (info) >0.5 and minor allele count (MAC) ≥3 were included in the analysis. In total, 48,943 unrelated individuals passed all quality control steps and were used in this analysis.