MR-base is a database and analytical platform for Mendelian randomization being developed by the MRC Integrative Epidemiology Unit at the University of Bristol.

You can either use the web application or our TwoSampleMR R package.

Launch MR-Base webapp R package beta!

Note - by clicking the "Launch MR-Base webapp" button you consent to the use of a cookie which enables us to ensure you have consented to the terms and conditions of data access. Information about how to control or delete cookies can be found at

Telomeres paper published

Our paper reporting Association Between Telomere Length and Risk of Cancer and Non-Neoplastic Diseases has been published in Jama Oncology. See the publications page to access supporting data.

Software Citations


Gibran Hemani, Jie Zheng, Kaitlin H Wade, Charles Laurin, Benjamin Elsworth, Stephen Burgess, Jack Bowden, Ryan Langdon, Vanessa Tan, James Yarmolinsky, Hashem A. Shihab, Nicholas Timpson, David M Evans, Caroline Relton, Richard M Martin, George Davey Smith, Tom R Gaunt, Philip C Haycock, The MR-Base Collaboration. MR-Base: a platform for systematic causal inference across the phenome using billions of genetic associations. bioRxiv. doi:


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