The patient has always resided at the heart of medical practice. Historically, however, treatment protocols have been largely determined not by the individual patient but by research derived from large patient population studies.
With the mapping of the human genome, though, such standards and practices have begun to change, giving rise to genetics-informed practices. Researchers and practitioners alike argue that the standard model of evidence-based medical practices may soon be supplanted by a more effective approach tailored to the unique genetic makeup of the individual patient.
This article examines the role of genetics in current and future medical practice. It also examines the question of whether, and to what extent, genes can determine which medicines will work for you.
Personalized Medicine
The basis of modern medical practice in population research has yielded profound advances in our understanding, treatment, and prevention of disease. As such, evidence-based medicine has saved untold numbers of lives and has contributed to the health and healing of countless patients worldwide.
For all of these advancements, however, evidence-based approaches have been unable to accommodate the innumerable and often unpredictable variations within patient populations. This has meant, historically, that the practice of medicine has been largely a game of numbers and statistics.
Unfortunately, though, patients who happen to be outliers, those who happen to fall outside of the statistical mean, are likely to have experienced ineffective or even inappropriate treatments, with sometimes catastrophic results.
For these patients, the results of inappropriate, statistics-based treatments can encompass everything from adverse treatment reactions to fatal disease progression. It is for this reason that the rise of personalized medicine has been so widely celebrated. A principal element of personalized practice is the use of DNA tests to customize treatment plans to the patient’s unique genetic makeup.
Through genetics-based personalized medicine, proponents assert, practitioners will be able to better identify the therapies to which the patient will be most responsive, plus the most adequate dosage for him or her. That’s why they support the combined use of pharmacogenetics and personalized medicine. At the same time, the patient’s genetic tests can be used by the healthcare provider to determine which treatments are likely to produce little effect on the patient or, worse, to instigate an adverse response, such as a potentially life-threatening allergic reaction. We would therefore also be talking about individualized medical therapy and pharmacogenetics.
Similarly, genetic testing can be used to identify health risks unique to the patient. Drug reactions are highly influenced by each individual’s unique genetics. This includes identifying the presence of gene variants, known as SNPs, responsibles for certain forms of cancer, including breast, ovarian, and colon cancers.
Pharmacogenomics
One of the most promising arenas of personalized medicine is that of pharmacogenomics. pharmacogenomics refers to the design, development, and prescribing of therapeutics in alignment with the individual patient’s genetic sequencing.
The ultimate goal of pharmacogenomics is to maximize the efficacy of therapeutics while minimizing side effects and avoiding adverse reactions. This may be done, for instance, through the study of gene sequences known to influence how the liver absorbs and metabolizes certain pharmaceutical compounds.
If the patient is missing a crucial gene or has expressed a genetic enzyme that decreases their body’s ability to metabolize the active ingredients of a standard therapeutic, then the clinician can prescribe an alternative course without having to wait for evidence of standard treatment failure.
The study of a patient’s genes to better predict the efficacy of standard, as well as alternative courses of treatment is based on the search for pharmacological compatibility through genetic testing and it is fundamental to the practice of personalized medicine.
Biological compatibility through genetic testing is also central to an innovative new genre of medicine: tissue engineering. Though still in its early phases, this branch of genetic medicine is giving new hope to those facing an array of life-threatening conditions, from severe burns to organ failure. It is hoped that, through tissue engineering, clinicians will be able to culture or grow cells and tissues that are genetically identical to the patient’s own, which is often the key to preventing rejection and promoting the health of the graft.
Enhanced diagnosis and disease prevention
As suggested above, genetic testing doesn’t just enable clinicians to choose a treatment regime most compatible with the patient’s individual physiology, but it can also support care providers in diagnosing and preventing disease.
Biomedical electronic techniques, for instance, are increasingly being used to support and enhance personalized medicine through the comprehensive analysis, monitoring, and application of the patient’s unique health information in designing patient-focused treatment plans.
For example, approximately 70 million Americans suffer from some form of digestive disorder. However, due to the wide variation in symptomatology from one patient to another, large segments of the population may experience a delayed or missed diagnosis. This leaves many to suffer, sometimes for years, with improper treatment — or no treatment at all.
Food sensitivities and intolerances, such as gluten or lactose intolerance, can be exceptionally difficult to diagnose through traditional means. A clinical genetic screening, however, can quickly diagnose gluten intolerance and other sensitivies with a high degree of accuracy, enabling patients to begin a treatment regime that can restore their health and overall quality of life.
The takeaway
The future of medicine may well lie in your genes. Genetics are increasingly playing a key role in the development of pharmaceuticals, in diagnosis and prevention of disease, and in formulating the most effective treatment plans. What this means, ultimately, is that genetics-focused personalized medicine may well usurp population-based practice.
Author: Sam Bowman
