Table 3. Association of genetic risk score and SAD risk in the testing set.

	# of subjects (SAD/Controls)	Mean GRS		Median GRS
Sample set		SAD	Controls	SAD	Controls	P value	AUC
GRS based on 6 SNPs	227/378	2.48	1.15	0.85	0.55	<0.001	0.63
APOE ε4 carriers	93/81	4.57	2.47	2.51	1.69	0.003	0.64
APOE ε4 non-carriers	134/297	1.03	0.79	0.53	0.47	0.101	0.55
Modified GRS based on 3 non APOE-related SNPs	227/378	1.02	0.91	0.87	0.87	0.002	0.58
APOE ε4 carriers	93/81	1.01	0.92	0.87	0.87	0.187	0.56
APOE ε4 non-carriers	134/297	1.02	0.91	0.87	0.87	0.006	0.58

Abbreviation: SAD, sporadic Alzheimer's disease; GRS, genetic risk score