PREIMPLANTATION GENETIC TESTING FOR POLYGENIC RISK IN TYPE 1 AND TYPE 2 DIABETES: A SYSTEMATIC REVIEW OF METHODOLOGIES, CLINICAL OUTCOMES, AND ETHICAL CONSIDERATIONS

Main Article Content

Afrin Yasmin

Keywords

Preimplantation Genetic Testing, Polygenic Risk Score, Type 1 Diabetes, Type 2 Diabetes, Embryo Selection, Genomic Medicine, Ethical Considerations

Abstract

Background: The global prevalence of diabetes mellitus continues to rise, with Type 1 diabetes (T1D) and Type 2 diabetes (T2D) imposing significant health and economic burdens. While preventive strategies such as lifestyle modification and population-level screening have had limited success, advances in genomics offer new possibilities for risk reduction. Preimplantation Genetic Testing for Polygenic Disease Risk (PGT-P) is an emerging technology that integrates polygenic risk scores (PRS) into in vitro fertilization (IVF) protocols to rank embryos by predicted susceptibility to complex diseases such as diabetes.


Objective: This systematic review synthesizes evidence published between 2015 and 2025 on the methodological foundations, clinical utility, and ethical considerations of PGT-P for reducing polygenic risk of T1D and T2D in offspring.


 Methods: Systematic search was conducted through PubMed, Scopus, Web of Science, and Embase for peer-reviewed literature using combinations of terms including “PGT-P,” “polygenic risk score,” “embryo selection,” “Type 1 diabetes,” and “Type 2 diabetes.” Eligible studies were screened and appraised independently by two reviewers. Data on study characteristics, methodology, risk reduction outcomes, accuracy, and ethical implications were extracted and narratively synthesized following PRISMA 2020 guidelines.


Results: A total of 1,172 records were screened, of which 37 studies met inclusion criteria (PRISMA diagram, Figure 1). PGT-P demonstrated relative risk reductions of up to 72% for T1D and modest reductions for T2D, supported by >99% genotyping accuracy. Ethical concerns included informed consent, access equity, ancestry bias in PRS models, and the probabilistic nature of predictions. Gaps in regulatory and policy frameworks were evident across jurisdictions.


Conclusions: PGT-P represents a promising step toward proactive, personalized prevention of diabetes, but its clinical implementation demands rigorous validation, robust ethical oversight, and policies to ensure equitable access and responsible use.

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