Post-hoc analyses stratified by APOE status revealed that the effect of AD PRSp<1 on slope in task performance was strongest in APOE ε4 carriers (n = 78, t = − 2.8, p = 0.0056) , with a trend-level effect in non-carriers (n = 213, t = − 1.8, p = 0.067). The gene discussed is APOE; the disease is Alzheimer disease.