Figure 1.

Simplified One-Carbon Metabolism. Metabolites included in the model predicting log(HOMA-IR) concentration are indicated in purple, and the gene of interest is annotated within a yellow hexagon. In brief, the methionine cycle is involved in methyl-transferase reactions, the folate cycle is involved in purine synthesis, and the transsulfuration pathway culminates with formation of the antioxidant glutathione (9). The figure was created with Biorender.com. MTHFR, methylenetetrahydrofolate reductase; THF, tetrahydrofolate.