TBC1D4-Related Monogenic Diabetes: Molecular Mechanisms, Clinical Recognition, and Therapeutic Implications

Monogenic diabetes caused by TBC1D4 mutations is a relatively rare hereditary disorder of glucose metabolism that has increasingly gained attention in recent years. The protein encoded by this gene plays a pivotal regulatory role in glucose transport within skeletal muscle and adipose tissue; its dysfunction leads to significant insulin resistance and glucose dysregulation characterized by predominant postprandial hyperglycemia. Accumulating research indicates that TBC1D4 mutations may contribute to metabolic disturbances by impairing glucose transport and blunting cellular insulin sensitivity. Patients typically present in adolescence or young adulthood, often accompanied by metabolic comorbidities such as obesity, dyslipidemia, fatty liver, and hyperuricemia; some may also manifest acanthosis nigricans or polyendocrine metabolic ovarian syndrome (PMOS; formerly polycystic ovary syndrome)-like features. Due to frequent clinical misdiagnosis or underdiagnosis, a comprehensive evaluation incorporating age of onset, family history, glycemic characteristics, autoantibody status, and genetic testing is essential for accurate diagnosis. Currently, specific targeted therapies are lacking, and lifestyle intervention remains the cornerstone of management, with exercise intervention being particularly vital for improving insulin resistance. This review focuses on the molecular biological characteristics of the TBC1D4 gene and its encoded protein, mutation types, pathogenic mechanisms, clinical manifestations, and diagnostic strategies, as well as therapeutic advances. It aims to systematically summarize the research progress on TBC1D4-related monogenic diabetes to enhance clinical awareness and provide a reference for early identification, precise diagnosis, and individualized treatment.