roughly 50%. A higher degree of sign concordance would suggest that at least some of the signal from the GWAS comes from true genetic effects. Across four sign tests, we strongly reject the null hypothesis of 50% sign concordance for all of the sign tests (P < 5 × 10−10 in all four tests), implying that at least some of the signal from the GWAS comes from true genetic effects. Our third test of population stratification, the “within-family regression test,” compares both the signs and magnitudes of the discovery and WF GWAS of general risk tolerance. The Supplementary Note, Supplementary Tables 28, 29, and Supplementary Fig. 13 provide further details on the three tests and report their results. All three tests imply no more than low levels of population stratification.
