Regarding diagnostic status, ALT levels (estimate = −0.195, SE = 0.048, p < 0.001) were significantly decreased, while the AST to ALT ratio (estimate = 5.506, SE = 1.236, p < 0.001) was significantly increased in AD compared with SCD in APOE ε4 carrier group (Table 4). The gene discussed is GPT; the disease is Alzheimer disease.