Brief Overview of the
Emergence of Pharmacogenetics


Drug labelled, Plavix

Pharmacogenetics ?

Pharmacogenetics isn’t just some scientific jargon; it’s the future of medicine that’s changing how we use drugs. Back in the day, doctors noticed that not everyone responds the same way to medicines. They figured out that our genes play a big role in this. This discovery rocked the world of medicine and how we treat diseases with drugs.

From the early days of understanding how genes affect our reactions to drugs to using genetic info to help doctors treat patients better, pharmacogenetics is reshaping how we think about medicines. It’s promising better and safer treatments, not just for some, but for folks all around the globe.

In this overview, we embark on a journey through the history and evolution of pharmacogenetics, shedding light on the key milestones and developments that have propelled it into the forefront of personalized medicine.

Drugs rearranged to DNA structure

1950s – 1960s: Early Investigations

  • The concept of pharmacogenetics began to gain attention as researchers observed individual variations in drug responses.
  • Studies focused on understanding why some patients experienced adverse reactions while others benefited from medications.
  • In 1957, The term “pharmacogenetics” was coined by Friedrich Vogel. Early studies focused on genetic differences in enzyme activity, such as variations in acetylation affecting drug metabolism.

1970s – 1980s: Genetic Variations and Drug Metabolism

  • Researchers identified genetic differences in drug-metabolizing enzymes, particularly the cytochrome P450 (CYP450).
  • Genetic polymorphisms (variation in our genes) were linked to variations in drug metabolism rates, affecting drug efficacy and toxicity.
  • Notable discoveries included the genetic basis for poor metabolizers of certain drugs like Debrisoquine (a medication that is primarily used to lower blood pressure and treat irregular heart rhythms).
  • Advances in molecular biology allowed for the identification of specific genetic variants. Studies linked polymorphisms in CYP2D6 to variable drug metabolism rates, influencing drug efficacy and safety.

1990s: Genetic Basis for Drug Responses

  • The Human Genome Project , initiated in the late 1980s and completed in the early 2000s, provided a wealth of genetic information.
  • Researchers began identifying specific genetic variants associated with drug responses, including variations in drug targets and receptors.
  • The term “pharmacogenetics” became more widely used to describe the study of genetic influences on drug responses.

2000s: Translational Advances and Clinical Implications

  • Advances in genotyping technologies and DNA sequencing allowed for more comprehensive studies of genetic variants linked to drug responses.
  • Pharmacogenetic testing gained attention for its potential to guide personalized medicine.
  • Organizations like the Clinical Pharmacogenetics Implementation Consortium (CPIC) and the Dutch Pharmacogenetics Working Group (DPWG) started publishing guidelines to help clinicians incorporate pharmacogenetic information into practice.
  • Regulatory agencies like the U.S. FDA started incorporating pharmacogenetic information into drug labels because the completion of the The Human Genome Project in 2003 provided a wealth of genetic information, facilitating the identification of pharmacogenetic markers. The FDA began to recognize the importance of pharmacogenetics in drug labeling, leading to more personalized medicine.

The image shown on the left represents a sample of pharmacogenetic information on a drug label.

2010s – Present: Integration into Clinical Practice

  • Pharmacogenetics transitioned into the broader field of pharmacogenomics, incorporating genomics and molecular biology.
  • Many hospitals and healthcare systems integrated pharmacogenetic information into electronic health records (EHRs) to aid decision-making.
  • The clinical implementation of pharmacogenetic testing grew, with tests guiding drug dosing, selection, and avoiding adverse reactions.
  • Research expanded to identify genetic markers for drug-induced side effects, optimal treatment outcomes, and cancer therapies.

SUMMARY

What do you think the transformation of Pharmacogenetics?

the field of pharmacogenetics has evolved from early observations of genetic differences in drug responses in the 1950s to a key component of precision medicine by the 2010s. Advances in genetic research, technological innovations, and regulatory support have facilitated its integration into clinical practice, improving patient care through more personalized and effective treatment strategies.

REFERENCE

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