Research into the role of plasma proteins on the human disease phenome is reported in Nature Genetics this week. Plasma proteins are known to be involved in a range of biological functions and have become a major source of druggable targets. To further investigate, a team led by scientists from the University of Bristol used Mendelian randomization (MR) and colocalization to estimate the effects of 1,002 proteins on 225 phenotypes, including 153 diseases and 72 risk factors.