Fig. 1: Analysis flowchart and the corresponding HCHS/SOL and ARIC analytic datasets.

We performed a multi-step analysis. Step 1: Identification of genetic associations with the MCI-MRS and BAIBA. Step 2: Association testing of the significantly associated genetic variants with MCI in a separate subset of US Hispanic/Latino older adults. Step 3: Assessment of generalizability of the genetic associations with MCI in European and African Americans from the Atherosclerosis Risk in Communities (ARIC) study. Step 4: Assessment of the mediation effect of BAIBA in the association of the genetic variants with MCI.