Clinical Genomics: Touching Every Practice

As genomic research becomes more granular and screenings more cost-effective, it is clear that clinical genomics is becoming widespread and useful in every practice across all specialties. “Genome-wide association studies are rapidly discovering new genetic markers to predict disease on a weekly basis,” says Dr. Michael F. Murray, coauthor of Clinical Genomics: Practical Applications in Adult Patient Care. Genetic screenings are not only useful for predicting the likelihood of diseases such as cancer; they are being used to predict far more common health concerns such as:

  • High Blood Pressure: Rare variants of genes with substantial effects are responsible for hypertension, and often these genes lie within pathways managing sodium homeostasis.
  • Diabetes: Genetic variants have been identified that affect the body’s ability to modulate the pancreatic islet function.
  • Obesity: Genetic Investigation of Anthropometric Traits (GIANT) Consortium found more than 140 locations across the genome that play roles in various obesity traits.
  • Coronary Artery Disease: A comprehensive 1000 Genomes-based genome-wide association meta-analysis of coronary artery disease known CAD-associated genetic sequences and identified ten new ones.
  • Stroke: A study of almost 5,000 patients pinpointed a genetic variant tied to an increased risk for stroke.

Being able to predict which patients are genetically predisposed to these concerns increases the physician’s ability to monitor precursors and their ability to persuade patients to make lifestyle changes that will improve their overall health.

In addition to these broad, common health concerns, research is revealing causative or contributory gene variants in diseases such as epilepsy, cardiomyopathy, cancer, Charcot-Marie-Tooth disease, mental retardation, other neuropathies, metabolic disorders, and ALS (Lou Gehrig’s disease).

As new discoveries are made, patients will start to expect and demand early screening. With the rising costs of healthcare, clinicians will have to take an active role in requesting genetic screenings judiciously for those patients most likely to benefit from early knowledge. For example, genetic screening is not appropriate for rare disorders that seem to be the result of variants in a single gene. Therefore a working knowledge of what is possible with clinical genomics and how to best use genetic screening is required in every practice and specialty.

It’s unclear how effective interventions are currently in preventing the expression of these genes, but there have been some early successes. For example mutations in BRCA1 and BRCA2 genes often indicate high lifetime risk of breast and ovarian cancer. If a patient has a strong family history of breast cancer, genetic screening is recommended. Interventions available to patients who test positive include enhanced surveillance, medication use, and if necessary, surgery.

Many genetic screenings come up inconclusive and clinicians need to be prepared to set expectations appropriately and counsel patients. At a minimum, clinicians need to learn what the test is, how it works, what it tells you (as well as what it won’t tell you), and how to use the results. Engaging genetic specialists as part of the clinical team will also become more common and necessary since clinical genomic advances are so rapid.

For more information on how primary care physicians can incorporate genomics into their practice, check out this free white paper: Primary Care and Genomics: How Will Advances in Genomics Affect the PCP’s Daily Practice and What Can We Do to be Prepared?

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