Pharmacogenetics: past, present and future

Pharmacogenetics, also now known as pharmacogenomics, is the study of genetic variability in the response to drug treatment.

It has a long and varied history as researchers have discovered more about genetic variability among humans and how this can affect response to medications and other substances. It has the potential to make great improvements to the healthcare system in the future, but more research is needed at this time to set this into motion.

Past

The first recorded association with pharmacogenetics dates back to 510 BC when Pythagoras noted that ingestion of fava beans proved fatal in selected individuals, but was not a widespread result. This was later discovered to depend on the genome of different individuals, specifically a deficiency in G6PD.

The rules of heredity were established in 1866, setting the research and knowledge about pharmacogenetics into motion.

Throughout the 20th century, there were several breakthroughs in the field, including the discovery of glucose-6-phosphate deficiency and other inherited defects in metabolism, which may affect an individual’s response to a medication.

The terminology of “pharmacogenetics” for the genetically determined response to pharmaceutical products was not introduced until 1957.

The Human Genome Project began in 2000 and was published in 2003, which was a large collaboration targeted at understanding the effects that the human genome can have on physiological functions, particularly the response to pharmaceuticals.

Present

Recently, the term pharmacogenomics has seen an increase in use, rather than pharmacogenetics, and has been included in the title of several journals on the subject.

It is currently viewed as an important area for scientific research, as the promise of targeting drugs according to the specific genetic makeup of each patient has tangible benefits in practice, if able to be implemented correctly.

At this point in time, we are beginning to understand more about variation in the human genome, but the specific applications of how we can manipulate these discoveries to our advantage are still in progress. Most research to date has focused on the potential of variations in the single nucleotide polymorphisms (SNPs) to determine individual drug response, and there is already an extensive publicly available database on the topic.

However, pharmacogenomics continues to be a promising solution and is not widely used in medical practice. Instead, drugs are typically prescribed on a general basis, according to the height and weight of the individual, rather than their genome.

Future

With continued research and developments in the field of pharmacogenomics, it is likely that this knowledge will be utilized in the prescription of drugs in the future.

Profiles of SNP variations may enable tailored prescription of medications to specifically cater to the needs of each individual. This has the potential to optimize the efficacy of the treatments, while reducing the risk of side effects and toxicity.

However, before pharmacogenetics can be integrated into primary healthcare and prescribing, further research needs to be undertaken. Although our expectations are high there are a number of practical issues that need to be addressed in the future, including the large number of variations that may affect a patient’s response to a drug.

It is hoped that the future will bring more conclusive research into the field of pharmacogenomics, and set the motion of its integration into medical practice. The results have high positive potential to improve patient response to medication and overall healthcare.

References

• http://www.ncbi.nlm.nih.gov/pubmed/21884816
• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2014592/
• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2014592/table/tbl1/
• http://pharmrev.aspetjournals.org/content/63/2/437.full
• http://www.yourgenome.org/facts/what-is-pharmacogenomics

Further Reading

• All Pharmacogenetics Content
• Personalized medicine and the Human Genome Project

Written by

Yolanda Smith

Yolanda graduated with a Bachelor of Pharmacy at the University of South Australia and has experience working in both Australia and Italy. She is passionate about how medicine, diet and lifestyle affect our health and enjoys helping people understand this. In her spare time she loves to explore the world and learn about new cultures and languages.