We found that serum TMAO levels were significantly increased in both ABX + FMT-APP/PS1 and ABX + FMT-AD groups of mice compared to the ABX group (ABX vs. ABX + FMT-APP/PS1, P = 0.0043; ABX + FMT-AD vs. ABX, P = 0.0232) (Figure 2E). The gene discussed is APP; the disease is Alzheimer disease.