Experience the new features (beta version)!

Added the --vif-threshold option to filter redundant (i.e., multicollinearity) covariates using the Variance Inflation Factor (VIF).
Added the --export-random-eff option to export individual's random effects from the heritability estimation model.
Added the --output-significant-qtls option to extract significant variant-phenotype pairs.
Added support for separately setting --dprop-pc-covar for genotype and phenotype PCs selection.