Is HLA-DQ2 useful for fatigue?

HLA-DQ2 is a genetic marker strongly associated with celiac disease, which can cause fatigue through malabsorption, chronic inflammation, or associated conditions. However, about 30% of the general population carries HLA-DQ2, yet only a minority develops celiac disease. Therefore, testing for HLA-DQ2 alone is not useful for diagnosing or managing fatigue. It may have clinical value only when celiac disease is suspected, alongside serology and duodenal biopsy. The evidence for the celiac link is human-strong, but for fatigue as an isolated symptom, the connection is indirect and moderate. Consumer DNA tests often overstate the relevance of this marker. Important: do not start a gluten-free diet based solely on this genotype, as it can lead to nutritional deficiencies or unnecessary restrictions. For persistent fatigue, a comprehensive medical workup (CBC, iron, B12, thyroid) is recommended.