RT Journal Article SR Electronic T1 Mendelian randomisation supports causal link between obesity and asthma JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 194 OP 195 DO 10.1136/thoraxjnl-2019-214164 VO 75 IS 3 A1 Diana A van der Plaat YR 2020 UL http://thorax.bmj.com/content/75/3/194.abstract AB