To illustrate the biological insights enabled by qQTL analysis, we examined regulatory effects at candidate AD risk genes where distributional genetic effects were detected but linear associations were weak or absent, including PITRM1, a simple variance QTL completely missed by linear analysis and TMEM106B, exhibiting lower-quantile-specific effects in excitatory neuron combined with interaction effects. This evidence concerns the gene PITRM1 and Alzheimer disease.