Nov 16, 2010 - Research

How People React to Personal Genetic Information

During his presentation at the annual meeting of the American Society of Human Genetics (ASHG), National Institutes of Health Director Francis Collins was open about his genotype at the TCF7L2 marker associated with diabetes, noting that he has the “riskier” TT genotype.  Such openness about personal genetic information is consistent with a trend towards increasing comfort with personal genetic information. That trend was in evidence at the ASHG conference, which was attended by more than 7000 scientists, physicians, students and exhibitors.

Several studies presented at the conference focused on reactions people have to receiving personal genetic information.  One study, conducted by David Kaufman and colleagues, was based on a survey of customers of 23andMe and two other companies.  The following four themes are among a number that emerged from the presentations and discussions:

1) People want to be able to decide on their own whether genetic information might be useful to them, rather than have an expert decide for them.

Some participants in the ASHG meeting questioned the value of obtaining personal genetic information.  They argued that while some genetic tests are predictive, many tests have not been proven to lead to better clinical outcomes. Several scientists, however, have argued that personal utility (a subjective measure) is more relevant than clinical utility (where cost and clinical outcomes are used to calculate utility).  Scott Roberts noted that the personal utility of genetic information may take the form of increased awareness of disease/health risks, more informed health planning, psychological relief, or simply the feeling that “knowledge is power.”

A few of the studies presented at the meeting suggest that people do find value in personal genetic information, even when it isn’t highly predictive. When David Kaufman and colleagues at the Genetics and Public Policy Center at Johns Hopkins University asked customers of 23andMe, Navigenics, and DeCodeMe about their motivations for purchasing a personal genome service (PGS), curiosity was high on the list (followed by health concerns related to medical issues in family members).  Ninety percent of customers reported that their curiosity was satisfied, and less than 2% were unsatisfied with the overall personal genome service they had received.

In a separate study, S. C. Sanderson of Mount Sinai School of Medicine surveyed 131 college students who smoke, and found that even though the students understood that a GSTM1 variant associated with lung cancer risk is not highly predictive, they were nonetheless interested in obtaining their genotype for that variant.  These preliminary results suggest that there is interest in a broad array of genetic information.

2) Customers of direct access personal genomics services (PGS) generally understand the results they are receiving.

A question in the minds of many is how well consumers understand personal genetic information.  David Kaufman and colleagues found that when they presented PGS customers with hypothetical sets of results for two different individuals, 93-95% of the study participants correctly interpreted the results. Furthermore, advanced education was not a prerequisite for — nor a guarantee of — understanding; people without college degrees understood the information more than 90% of the time, and people with postgraduate degrees still made mistakes. A study of individuals participating in the Coriell Personalized Medicine Collaborative (CPMC) conducted by Barbara Bernhardt of the University of Pennsylvania reached similar findings. While 23andMe is excited that these preliminary findings show that people generally understand their genetic information, we are constantly striving to improve how we communicate this information to customers.

3) Early studies indicate that people are not overly anxious about the personal genetic information they have received.

The REVEAL study, which celebrated its 10th year at the ASHG meeting, has gathered extensive data regarding emotional responses to personal genetic information, finding that there is little difference in anxiety levels between people who learn that they have a genetic variant that puts them at higher risk of Alzheimer’s disease and people who learn that they do not. However, this study focused on a single genetic variant, involved relatives of individuals with Alzheimer’s disease, included presentation of results in person or via telephone, and excluded individuals who had a history of anxiety or depression, and so results may not extend to direct access personal genome services.

In contrast, in the study conducted by Barbara Bernhardt and her colleagues, individuals received results for multiple genetic variants associated with multiple diseases, where participants were not selected for having a particular family history.  The researchers found that no participants in this study reported being overly concerned about their risks based on genetics. While small, this study is among the first to evaluate emotional responses to results from a set of multiple genetic tests associated with multiple disorders.

4) Many customers of direct access personal genomics services are motivated to make positive changes in health-related behaviors.

The study conducted by Barbara Bernhardt and colleagues found that about a third of the participants who received personalized genetic risk information responded by making a positive change in health-related behaviors. Most were making small changes such as exercising more. Most of those who said that they weren’t making changes said they felt that they were already doing the right thing.  Similarly, the study conducted by David Kaufman and colleagues found that about a third of PGS customers were being more careful about their diet, 15% had modified their intake of medications or supplements, and 14% were exercising more.  The REVEAL study found evidence of increased exercise in response to communication of both Alzheimer’s disease risk and cardiovascular disease risk associated with a specific genetic variant.

At a press briefing about these findings, a reporter asked the panel of scientists if people were wasting money on direct-to-consumer genetic services.  Bernhardt replied that if people’s curiosity is satisfied, and if people are making positive changes in health-related behaviors, then that is a good outcome.  Kaufman added that 90% of the PGS customers in his study responded that the service was worth the price.  And Andrew Faucett of Emory University, who spoke separately on oversight of genetic testing, replied that if the service helps people start a conversation with their physician, that’s good.

In summary

There is still much to be done in terms of better understanding how people interpret personal genetic information and what factors influence their reactions.  For instance, the jury is still out on whether or not obtaining personal genetic information leads to improved health-related behaviors in the long term.  But the early studies reported last week at the ASHG meeting are an exciting step towards that understanding.

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