A SYSTEMATIC REVIEW OF TCF7L2 GENE POLYMORPHISMS ASSOCIATED WITH TYPE 2 DIABETES MELLITUS IN ASIAN POPULATIONS

Fae Marie L. Cablao¹; Louis Genesis B. Patdu¹; Zyrene Joy Ethel Arobio¹; Gecelene C. Estorico¹; ²

doi:10.5281/zenodo.21246194

Abstract

Type 2 Diabetes Mellitus (T2DM) is a multifactorial metabolic disorder influenced by genetic and environmental factors. This systematic review aimed to synthesize the available evidence on the association between TCF7L2 gene polymorphisms and susceptibility to T2DM among Asian populations. A systematic literature search was conducted following the PRISMA 2020 guidelines using PubMed, Scopus, Web of Science, ScienceDirect, and Google Scholar. Peer-reviewed studies published from 2019 to 2026 were screened based on predefined eligibility criteria. Methodological quality was assessed using the Newcastle–Ottawa Scale (NOS) and the Joanna Briggs Institute (JBI) Critical Appraisal Checklist. Fifteen studies met the inclusion criteria and were included in the qualitative synthesis. The findings consistently identified rs7903146 as the most frequently associated polymorphism with increased T2DM susceptibility, while rs12255372, rs4506565, rs11196205, and rs7901695 were also associated with impaired glycemic control, β-cell dysfunction, insulin resistance, dyslipidemia, and other adverse metabolic outcomes. Several studies further highlighted the potential of TCF7L2 variants for genetic risk assessment and personalized therapeutic strategies. Overall, the included studies demonstrated moderate to high methodological quality, supporting the role of TCF7L2 polymorphisms as important genetic markers of T2DM susceptibility in Asian populations. Further large-scale, multi-ethnic prospective studies are recommended to strengthen the current evidence.

Keywords

β-cell dysfunction; insulin resistance; glycemic regulation; precision medicine; pharmacogenomics; genetic screening

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