RT Journal Article
SR Electronic
T1 Searching for the causal effects of BMI in over 300 000 individuals, using Mendelian randomization
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 236182
DO 10.1101/236182
A1 Louise A C Millard
A1 Neil M Davies
A1 Kate Tilling
A1 Tom R Gaunt
A1 George Davey Smith
YR 2017
UL http://biorxiv.org/content/early/2017/12/19/236182.abstract
AB Mendelian randomization (MR) has been used to estimate the causal effect of body mass index (BMI) on particular traits thought to be affected by BMI. However, BMI may also be a modifiable, causal risk factor for outcomes where there is no prior reason to suggest that a causal effect exists. We perform a MR phenome-wide association study (MR-pheWAS) to search for the causal effects of BMI in UK Biobank (n=334 968), using the PHESANT open-source phenome scan tool. Of the 20 461 tests performed, our MR-pheWAS identified 519 associations below a stringent P value threshold corresponding to a 5% estimated false discovery rate, including many previously identified causal effects. We also identified several novel effects, including protective effects of higher BMI on a set of psychosocial traits, identified initially in our preliminary MR-pheWAS and replicated in an independent subset of UK Biobank. Such associations need replicating in an independent sample.