What role does FUT2 play in Fruchtbarkeit?

FUT2 (fucosyltransferase 2) determines secretor status, i.e., whether fucosylated antigens are present in body fluids like saliva, mucus, and breast milk. This influences gut and vaginal microbiome composition. Some observational studies suggest a link between non-secretor status (inactive FUT2) and increased risk of recurrent urinary tract infections, bacterial vaginosis, and possibly fertility issues. The mechanisms may involve altered immune responses or impaired absorption of nutrients like vitamin B12. However, the evidence for a direct role of FUT2 in fertility is weak and insufficient for clinical recommendations. Most data come from population-based studies without control for confounders. A genetic test for FUT2 variants (e.g., rs601338) cannot be used as fertility diagnostics. Fertility is influenced by many factors including age, hormones, lifestyle, and medical conditions. FUT2 is an interesting but not decisive factor.