Chunk #26 — Polygenic Risk Scores: A Bridge Between Population Variation and Individual Differences — PRS Practicalities — Technical Considerations. — Improvements in PRS estimation:
meta-analysis, enables the joint analysis of several traits, resulting in improved PRS precision. MTAG takes advantage of the increasing number of publicly-available GWAS summary statistics, and the development of techniques which can estimate trait heritability and genetic correlations from summary statistics [LDSR; (Bulik-Sullivan et al., 2015), see also related user-friendly online interfaces/databases (e.g., LD Hub; http://ldsc.broadinstitute.org/ (Zheng et al., 2017)]. Indeed, early analyses have successfully applied MTAG to the study of several psychiatrically relevant traits, resulting in prediction accuracy improvements of 25–50% and increased numbers of genomewide significant hits ((Hill et al., 2017, Turley et al., 2017). Beyond these two examples, several approaches incorporating Bayesian estimation (Mak et al., 2016, So and Sham, 2017) and machine-learning (Pare et al., 2017, Shi et al., 2016), have also been proposed.
