Evidence check: HLA-DQ2 in the context of fertility

HLA-DQ2 is a genetic risk marker for celiac disease, not a direct fertility marker. Some studies link undiagnosed celiac disease with fertility issues, but the effect is indirect and affects only a minority of HLA-DQ2 carriers. Most individuals with HLA-DQ2 never develop celiac disease, and even in celiac patients, fertility often normalizes on a gluten-free diet. A genetic test for HLA-DQ2 alone has no clinical utility for fertility. Evidence: human-moderate (celiac-fertility association), but weak for HLA-DQ2 alone. Caution against overinterpretation.