Educating Physicians About Genomics: Are We Doing Enough?

Ricki Lewis, PhD

Disclosures

March 25, 2013

In This Article

What Should Physicians Know?

A workshop convened by the National Institutes of Health, the Centers for Disease Control and Prevention, and the Health Resources and Services Administration on the incorporation of genetics and genomic medicine into maternal and child healthcare found that "...many primary care providers lack knowledge, training, experience, and confidence in providing genetics-based services, ranging from understanding of basic genetics to collecting and interpreting family health histories and to ordering, interpreting, and acting on genetic tests."[2]

The report's recommendations emphasize that physicians need to think outside the Mendelian box and consider genetic contributions to all illnesses. It also points out a "lack of enthusiasm about genetics and genomic medicine among both trainees and those already in practice," which "may significantly limit the effectiveness of education efforts."

The workshop was held in June 2009, when direct-to-consumer genetic testing was in its infancy and when many of the newer targeted therapies and pharmacogenomics testing strategies were not widely available. As the use of genetic testing has evolved, so has the understanding of what current and prospective physicians need to know.

A big challenge is to sort through DNA-based tests to present those that students might realistically encounter and that are clinically actionable. "Knowing that making a decision based on genetic information will make a difference in clinical outcome is where the real activation energy is for a physician," said Dr. Scott of the University of Miami. "Why spend time learning about a test if it isn't shown to benefit anyone yet?"

Pharmacogenetic tests are likely to top the list, because predicting drug efficacy and adverse effects can inform treatment selection anywhere, even in an urgent care setting, said Dr. Scott.

But patients may not know the difference between a test that is actionable from one that is merely informational, so physicians should be prepared to help explain. Genome-wide association study (GWAS) results provide a good example of the confusion. These studies compare many genetic markers (typically single-nucleotide variants) among large numbers of people with a condition to controls, coming up with an "association" -- which a patient may misinterpret as a correlation or even a cause. And some GWAS results fall apart over time, when larger populations are considered.

Should a physician be expected to interpret a GWAS? "I'm not so sure they need to," said Dr. Korf. "I would hope that their medical education would teach them the principles of what GWAS is and its limitations, but they need to refer to a colleague who is a genetic counselor or a physician who is a clinical geneticist."

But knowing how to interpret test results from a direct-to-consumer company that report elevated risks could be useful. For example, a test for atrial fibrillation offered by 23andMe is based on a "preliminary research report" on a study of 333 people in Hong Kong that indicates a 1.4-fold increased risk -- in that group.

"The concepts of risk, absolute or relative, probability and so forth, aren't easily or formally taught in medical school," said Dr. Pyeritz. "Studies date back many years that show physicians are woefully undereducated in concepts of risk and interpreting what a relative risk of 1.2 means for a patient, whether based on genotype or something else."[3]

Although a detailed discussion about risk assessment may not come up for all physicians in everyday practice, a good starting point would be knowing how to explain the difference between a GWAS-derived risk assessment and results of a traditional carrier test for an inherited condition.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....