Public Views on Genetics and Genetic Testing: A Survey of the General Public in Belgium

Introduction

Over the past two decades, the field of medical genetics has seen transformative developments, such as the completion of the human genome project and the emergence of next-generation sequencing technologies (Collins and McKusick, 2001; Margulies et al., 2005; Koboldt et al., 2013). These important milestones have significantly accelerated research into human genetics, elucidating the genetic basis of many medical conditions.

Improvements in our understanding of medical genetics have opened up new avenues for using genetic testing (GT), beyond traditional clinical diagnostic purposes. Some of these recent applications of GT include presymptomatic/predictive testing of healthy individuals for susceptibility to develop a disease later in life, pharmacogenomic and nutrigenomic GT aimed at optimizing medical treatment and diet, respectively, based on one's genetic makeup (National Institutes of Health, 2010; Collins et al., 2014). Moreover, recent developments in human genetics have revolutionized GT for reproductive purposes, such as through carrier screening for monogenic recessive disorders, where individuals or couples can now be tested for the carrier status of hundreds of recessive conditions that may affect their children (Srinivasan et al., 2010; Martin et al., 2015; Nazareth et al., 2015; Silver et al., 2016).

On an individual level, GT may hold both medical and psychological benefits, such as increasing sense of control over one's life and, where possible, allowing deciding on various preventive measures (Houfek et al., 2015). For example, individuals may choose to modify their lifestyles (e.g., adopt a healthy diet and regular exercise in the presence of an increased risk for heart disease or diabetes; O'Daniel, 2010), undergo preventive medical procedures (e.g., prophylactic mastectomy in women at risk of developing breast cancer; Di Prospero et al., 2001), or alter future reproductive plans (in the context of carrier screening; Nazareth et al., 2015). From a public health perspective, GT is appealing due to its potential to foster prevention-based medicine, thus minimizing costs associated with medical treatments and improving the overall health of the population (Zimmern and Khoury, 2012).

Some of the disadvantages of GT include psychological distress associated with the procedure, potential harm due to unnecessary medical interventions where tests results are inaccurate (Botoseneanu et al., 2011), and the possibility of discrimination against individuals with particular genetic predispositions (Wauters and Van Hoyweghen, 2016).

Given the potential benefits and harms of GT, it is important to investigate the acceptability of this technology among healthcare users, such as the members of the general public (Etchegary et al., 2013).

Recent literature reviews have identified a large number of empirical studies on attitudes toward GT (Haga et al., 2013; Sweeny et al., 2014). Most of these studies focus on GT for specific medical conditions or particular demographic groups. In contrast, only a handful of studies have surveyed members of the public on GT more broadly. Additionally, results of previous attitudinal studies cannot necessarily be readily applied to any particular context for two reasons. First, the public's views on GT tend to evolve over time (Henneman et al., 2013). Second, populations in different countries may hold diverging views and beliefs about GT due to differences between healthcare systems and varying exposure to critical debates on GT (Miettinen and Väliverronen, 1999).

The present study was conducted with the goal to explore the attitudes of the Belgian general public toward various aspects of medical GT.

Materials and Methods

Results

Discussion

To our knowledge, this is the first exploration of attitudes of the general public in Belgium toward genetics and GT. Our study sample of 1182 individuals was representative of the Belgian population in terms of age and gender.

While nearly two-thirds of our study participants were curious about their genetic predisposition to diseases, the proportion of those interested in taking predictive GT was somewhat lower (39.1% for general predictive GT and 49.5% for GT for treatable/preventable disorders). This could be due to barriers to GT, which may include the cost of the test (Cherkas et al., 2010), time required for the procedure and follow-up (Foster et al., 2004), and for some individuals, concerns about potential misuse of test results (Suther and Kiros, 2009). Additionally, as we did not ask the respondents to assume a perfectly accurate test, it is possible that for some of them, obtaining results of a predictive genetic test did not equate to receiving reliable information about their predisposition to diseases. In earlier studies, interest in predictive GT has been shown to increase as the accuracy of the test approaches 100% (Condit, 2010).

Our findings also confirm the observation reported by others that members of the general public express higher interest in GT for preventable or curable disorders, as opposed to predictive GT either generally or for incurable genetic conditions (Shaw and Bassi, 2001; Singer et al., 2004; Makeeva et al., 2010; Botoseneanu et al., 2011; Vermeulen et al., 2014).

Of all genetic tests discussed in the questionnaire, our respondents expressed the greatest interest in reproductive GT, with ∼61% stating they would take a prenatal genetic test for all serious diseases with a view of possible termination of pregnancy and ∼54% indicating interest in preconception carrier screening for recessive disorders. Of note, younger (aged 41 or below) individuals in our study were significantly less likely to be interested in prenatal GT compared with both intermediate and older age groups. Although we did not ask our respondents about their future reproductive plans, it is reasonable to assume that prenatal GT was of the greatest personal relevance to those in the younger age group. Therefore, the lowest interest in prenatal GT among this group may suggest that respondents in our study were more likely to be approving of the general availability of this test than willing to personally use it. This appears to be consistent with earlier empirical studies, in which support for the general availability of reproductive genetic tests was usually higher than respondents' intention to use the test (Condit, 2010).

In the context of carrier screening for recessive disorders, we observed that despite high interest in this test (∼54%) and even greater support for making it available to all couples planning pregnancy (64%), approximately two-thirds of the respondents (67.8%) felt it was not irresponsible for prospective parents to refuse a carrier screening offer. One explanation for these findings could be that the decisions surrounding reproduction are considered intensely personal (Wilfond and Goddard, 2015) and given the implications of carrier screening for future reproductive choices, some respondents may have felt that the decision whether to participate in carrier screening is best left to the couples themselves.

Among the different types of genetic tests, we observed the lowest interest in having one's newborn child tested for diseases manifesting in adulthood. This is in contrast to the findings of two US-based studies reporting that most members of the general public prefer to receive all predictive genetic information about their youngest children, regardless of whether it is immediately relevant to the child's health (Goldenberg et al., 2014; Dodson et al., 2015). This difference may partly be attributed to the wording we used in the statement, which implied the distant and currently uncertain nature of medical benefits arising from such testing. Because of this, some respondents may have felt unsure as to whether performing a predictive GT during the newborn period for adult-onset disorders would be in the best interest of a child.

Our study also enquired about respondents' preferences among potential providers of GT. We observed a strong support for hospital-based GT performed exclusively with a doctor's prescription. Correspondingly, our respondents were against genetic tests being sold either by commercial providers over the internet or by a pharmacist. These results are similar to those reported in a survey of the Dutch public, where two-thirds of the respondents supported limiting GT to the hospital setting and <10% favored commercial GT through the internet or a pharmacist (Vermeulen et al., 2014).

One explanation for this may lie in the organization of healthcare services in Belgium and the Netherlands. In both countries, health insurance is universal and covers medical procedures deemed to be of clinical utility. Therefore, provision of genetic tests through established healthcare channels in these countries may enhance the sense of security for many individuals who may view this as an important precondition for accepting the test.

Our respondents voiced several concerns about potential negative implications of GT technologies. Nearly one-quarter (24%) of them indicated they were worried that genetic test results may fall into the wrong hands. This is similar to the findings of a survey carried out in the United States in 2000, where ∼25% of a large multiethnic population agreed that information from genetic tests is likely to be misused (Suther and Kiros, 2009).

Furthermore, a substantial minority of our respondents were worried about the possible negative impact of GT on disabled people, with 46% agreeing that due to GT, the society would grow less tolerant toward people with disabilities, while 40% believed that carrier screening for recessive disorders may devalue the lives of people affected with them. These results are comparable with the findings of the study by Henneman et al. (2013), in which 38% of the respondents agreed that there will be a dichotomy in our society: people with a good and people with a bad genetic predisposition.

Existence of such concerns clearly indicates a need for adequate policy and regulatory supervision of the implementation of GT technologies to safeguard against potential harms emanating from such developments. Of particular importance is ensuring that growing availability of reproductive GT bears no discriminatory messages against patients currently living with these disorders. To this end, it is essential that reproductive genetic tests, including carrier screening for recessive disorders, serve as a means for allowing prospective parents to make informed reproductive decisions, rather than as public health instruments aimed at preventing the birth of children affected with genetic disorders, since this may be interpreted as a negative value judgment about life with a disability (Janssens et al., 2015).

Finally, 71% of our respondents believed that carrier screening will lead to greater anxiety among would-be parents, and 31% considered carrier screening as excessive interference of medicine in pregnancy. These concerns are not new in the literature with respect to carrier screening and they have been seen as potential adverse psychosocial consequences of this technology (Verweij, 2008; Mosconi et al., 2014). It cannot be overemphasized that before deciding whether to take a carrier screening test, prospective parents should have access to high-quality information and, if required, face-to-face genetic counseling. This will help prospective parents weigh the advantages and disadvantages associated with carrier screening and make fully informed decisions in line with their personal values.

Conclusion

Respondents in our study expressed high interest in reproductive GT, such as prenatal testing and carrier screening for recessive disorders, whereas there was less interest in testing one's newborn child for predisposition to adult-onset diseases. We also observed that willingness to take a predictive genetic test for oneself was greater if testing was limited to treatable or preventable disorders. These findings suggest that the success with which different types of GT can be implemented is likely to vary as not all genetic tests will generate the same level of interest in the population. Therefore, it is important that the introduction of any new genetic test in the healthcare setting is preceded by careful assessment of the interest in and acceptability of the test among potential users.

Additionally, individuals' preferences among different forms of GT may help inform the development of guidelines and policies for the return of results by large-scale population biobanks. This is because biobanks may derive large amounts of health-related information from genomic data, which could be of varying interest to its participants.

According to a large majority of our respondents, genetic tests should be performed in a hospital with a doctor's permission, while commercial offers of genetic tests, either over the internet or through a pharmacist, are not permissible. Strong negative attitudes toward commercial GT offers may indicate that many members of the general public in Belgium are unlikely to pursue GT services outside the hospital setting. This highlights the need for rapid implementation of new genetic tests that have high clinical value into medical practice to provide the population with access to beneficial health-related interventions.

A substantial minority of our respondents were concerned that GT would stigmatize disabled people by fostering their image as individuals with undesirable genetic traits, while some were worried about potential misuse of test results. Since implementation of genetic tests is still in its infancy, at present, the validity of these concerns may be difficult to judge. Nevertheless, policymakers and regulators should be attentive to the concerns held by the general public and remain vigilant for potential societal harms emanating from new GT technologies. Additionally, continuous public education on genetics and routine provision of genetic counseling services to individuals undergoing GT have the potential to address some of the concerns associated with GT as well as dispel any misconceptions that members of the general public may hold regarding genetics and genetic tests.