ROLE OF GENETIC VARIATION IN DRUG RESPONSE

Genetic variation significantly influences individual responses to medications, affecting both drug efficacy and the risk of adverse reactions. This report reviews the role of genetic polymorphisms in drug metabolism, transport, and targets, highlighting key genes such as CYP2D6, CYP2C19, TPMT, and VKORC1. The integration of pharmacogenomics into clinical practice promises the advancement of personalized medicine, enabling the tailoring of drug choice and dosing based on a patient’s genetic profile. Furthermore, this report discusses the challenges associated with implementing pharmacogenetic testing, including technical limitations, cost-effectiveness, and ethical considerations. Overall, this review aims to provide an undergraduate-level understanding of the current knowledge, emerging research, and future perspectives in pharmacogenetics and personalized therapy, emphasizing the importance of genetic variation in optimizing therapeutic outcomes. This review also discusses the growing influence of emerging technologies, including next-generation sequencing, artificial intelligence–based predictive tools, and large-scale biobanks, which are accelerating discoveries in the field. These innovations are enabling more comprehensive analyses of genetic variation and providing deeper insights into gene–drug interactions. As research progresses, the development of standardized guidelines and the expansion of pharmacogenomic databases are expected to support more consistent and evidence-based clinical applications.

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