In the initial check of genetic overlap between the full and down-sampled summary statistics of the same trait, we found genetic correlations close to, but still significantly less than unity: 0.966 (SE = 0.007) for SMOK and 0.953 (SE = 0.012) for CANN,2 which motivated us to apply our approach to evaluate the comparability of the down-sampled summary statistics to those from the original paper.
