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Why can people respond differently to the same medication?

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The impact of the Human Genome Project on cancer research — Human Genome Project The Human Genome Project, which operated from 1990 to 2003, provided researchers with basic information about the genetic content of the human organism, opening new avenues of discovery in fields such as cancer research.

People respond differently to the same medication due to a variety of factors, including age, disease states, drug interactions, and individual genetics.1

A primary genetic driver of this variability is the presence of single nucleotide polymorphisms (SNPs), which are variations in a genetic sequence that occur in more than 1 percent of a population. These variations can alter cellular metabolism, potentially leading to ineffective treatment or dangerous drug responses.2

The field of pharmacogenomics specifically studies how these genetic differences among individuals cause varied responses to the same drug. Following the Human Genome Project, researchers have gained a deeper understanding of how an individual's unique genome influences their physiological response to medications. This knowledge has fostered the development of personalized medicine, an approach that uses genetic screening to select the most appropriate and effective drugs for a specific patient, thereby minimizing adverse reactions.342