For example, a study found that Collinsella correlates with higher serum levels of total cholesterol and low-density lipoprotein (LDL) cholesterol in healthy adults52, which may be correlated with the interaction between Collinsella and APOE. Functional studies that further explore the relationship between Collinsella, lipid metabolism, and inflammatory signals would help to elucidate how their interaction influences AD and other diseases. This evidence concerns the gene APOE and Alzheimer disease.