The summary statistics for the lipid traits were downloaded from http://csg.sph.umich.edu/abecasis/public/lipids2017/. For each trait k, the web portal contains variant-level genetic effect estimates for a given gene and their standard errors sek. We obtained Uk and Vk by using and sek as described in Summary statistics subsection of Methods. As the original genotypes from the study are not publicly available, we estimated the LD matrix R based on the genotypes of the European population from the NHLBI Exome Sequencing Project (ESP)37. To account for possible sample overlap among traits, we used Eq. (3) to estimate covariance among summary statistics across traits.
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