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Am J Public Health. 2006 November; 96(11): 1971–1978.
PMCID: PMC1751820

Public Willingness to Participate in and Public Opinions About Genetic Variation Research: A Review of the Literature

Abstract

Scientists are turning to genetic variation research in hopes of addressing persistent racial/ethnic disparities in health. Despite ongoing controversy, the advancement of genetic variation research is likely to produce new knowledge and technologies that will substantially change the ways in which we understand and value health. They also may affect the ways in which individuals and groups organize socially, politically, and economically.

Addressing concerns that may exist in different communities is vital to the scientific and ethical advancement of genetic variation research. We review empirical studies of public willingness to participate in and opinions about genetic research with particular attention to differences in consent and opinion by racial/ethnic group membership.

POLICYMAKERS HAVE described the integration of new genetic knowledge and technologies into the practice of public health and medicine as unavoidable.1 Newborn screening programs, prenatal testing, and genealogy documentation provide long-standing precedent for this integration. Scientists now are turning to research that seeks to understand genetic differences by racial/ethnic group membership (referred to as genetic variation research), in hopes of addressing persistent racial/ethnic disparities in health.

Researchers have criticized the lack of definitional clarity and inconsistent use of racial/ethnic group membership in US health research,2 while at the same time depending on these categories to define and explain disparities in health and health care.3 These categories generally include 1 or more of the categories used by the federal government, namely an ethnic group category—Hispanic/Latino—and several racial group categories—White American/White, African American/Black, Asian American, Native Hawaiian/Other Pacific Islander, and American Indian/Alaska Native—in addition to Other and more recently Mixed Race.

The proposed use of racial/ethnic group membership in genetic variation research has been widely debated. Advocates argue that significant genetic differences do exist by racial/ethnic group membership and that such information is critical to ensuring representative sampling.4,5 Advocates also propose that genetic variation research may lead to health benefits, such as improved understanding of disease susceptibility and targeted pharmacogenomic innovations.6,7 Critics raise methodological concerns about the validity of racial/ethnic group membership for studying genetic variation.810 Furthermore, critics assert that such research may encourage genetic determinism and scientific racism, divert attention from the powerful social and environmental determinants of health, and reinforce stereotypes about minority groups.1012

Despite ongoing controversy, the trajectories of genetic variation research are likely to produce new knowledge and technologies that will substantially change the ways in which we understand and value health. They also may affect the ways in which individuals and groups are organized socially, politically, and economically in society.13 Given this potential, strong arguments have been made in the literature for public consultation regarding the advancement of genetic science.1315 Consultation with racial/ethnic minority groups is particularly important given these groups’ past experience with the misuse of science. Addressing concerns that may exist in different communities is fundamental to the ethical advancement of genetic variation research and may facilitate the recruitment of diverse samples that are vital to answering the underlying scientific questions posed by genetic variation research.

What is known about the willingness of the public to participate in genetic variation research? Does willingness to participate in genetic variation research vary by racial/ethnic group membership? What concerns and other opinions do people have about genetic variation research? We present findings from a systematic review of empirical studies regarding US public willingness to participate in and opinions about genetic variation research and other genetic research and offer suggestions for future studies.

METHODS

We conducted preliminary searches for empirical studies of public willingness to participate in and opinions about genetic variation research in the National Library of Medicine Medline database and all databases under the Institute of Scientific Information Web of Science. Given limited results, we established broader parameters for a larger search using general search terms and including studies involving genetic research regardless of an explicit focus on variation by racial/ethnic group (Table 1 [triangle]). We excluded genetic research studies that referenced genetic testing (i.e., detection of specific genes or gene variants in individuals rather than in populations) but did not reference the donation or storage of genetic specimens for research (example16). Unlike the purpose and results of research involving genetic testing, the purpose and results of research involving specimen donation may not be shared with human subjects, particularly in the case of long-term storage. Furthermore, research involving specimen donation is less likely to offer human subjects the direct and immediate benefits associated with research involving genetic testing, such as test results, medical treatment, or other interventions. Therefore, findings from these 2 types of studies are not comparable.

TABLE 1
Search Strategy for Empirical Papers Regarding Public Opinions About and Willingness to Participate in Genetic Research: July–August 2005

We conducted systematic searches of the Medline and Institute of Scientific Information Web of Science databases during July and August 2005 using the parameters specified in Table 1 [triangle]. Search results, citations, and available abstracts for 2126 papers were downloaded into a citation database for review and tracking. Two authors reviewed titles and available abstracts. The vast majority of papers presented findings from gene prevalence studies in various populations. Thirty-three papers were selected as potentially relevant by at least 1 of the 2 authors during this initial review. Twenty papers were excluded because they were not empirical studies on willingness to participate in or opinions about genetic research (13 studies), they involved international populations (5 studies), or they were published only as abstracts (2 studies). Thirteen papers were determined to be relevant after full-text review.

Reference lists from the 13 relevant papers were reviewed for additional papers that may not have been captured by the database searches. Twenty-eight papers were identified in reference lists as potentially relevant, 1 of which was determined to be relevant after abstract or full-text review.17

Among the 14 relevant studies, 1 did involve genetic testing18 and was included because participants were informed that they would not receive test results and also were asked for consent to store DNA—2 features more typical of research involving genetic specimen donation. Finally, 1 relevant article identified in the preliminary search did not appear in the systematic search and therefore was not included in this review.19 This article did not use the terms race, ethnicity, or any variation (excluding 1 appearance of race in a table), nor did it have these terms assigned as keywords.

Findings from the reviewed studies are presented in 3 tables: Table 2 [triangle], studies reporting willingness to participate only; Table 3 [triangle], studies reporting willingness to participate and reasons for declining; and Table 4 [triangle], studies reporting opinions only. Study reference numbers appear in the tables and are used to discuss review findings.

TABLE 2
Descriptive Summary of Studies Regarding US Lay Public Willingness to Participate in Genetic Research (n = 7)
TABLE 3
Descriptive Summary of Studies Regarding US Lay Public Willingness to Participate in Genetic Research and Reasons for Declining Consent (n = 3)
TABLE 4
Descriptive Summary of Studies Regarding US Lay Public Opinions About Genetic Research (n = 4)

RESULTS

Our literature search produced 14 empirical studies on willingness to participate in and opinions about genetic research. Only 1 of these 14 studies made clear references to genetic variation research exploring relations among race, genes, and health.29 The purpose of most studies (10 studies) was to measure consent rates in response to requests for participation in genetic research (Tables 2 [triangle] and 3 [triangle]). Three of these 10 studies asked participants why they declined consent (Table 3 [triangle]), with 2 providing frequencies for reported reasons.18,26 Additional detail regarding participants’ concerns was described in 4 qualitative studies (Table 4 [triangle]). Finally, 8 of the 14 studies asked participants to consider specific information regarding the use of their DNA,18,2224,26,27 or a specific relation among genes, racial/ethnic group membership, or health.29,30

Sample Characteristics

There was limited racial/ethnic group diversity across studies; however, all studies included 1 or more racial/ethnic minority groups. African Americans constituted the entire sample of 3 studies,20,27,30 and Jews the entire sample of 1.24 Asian Americans and Native Hawaiians/Other Pacific Islanders were least represented,17,26,29 whereas American Indians/Alaska Natives were not represented in any of the studies. Six quantitative studies allowed comparisons in consent by racial/ethnic group membership,17,18,21,22,25,26 and only 1 study specified frequencies in different opinions by racial/ethnic group membership.28 Finally, 4 studies included former participants in health17,18,20 or genetic22 research, and 4 studies included participants personally affected by a genetic condition.20,22,25,30

Data Analysis

Studies providing the most detail about consent included frequencies and sociodemographic information by contact attempt, successful contact, and consent.22,23 One of these 2 studies also provided racial/ethnic group information for the population from which the sample was drawn and reasons for non-response.22 Seven consent studies included multivariate regression or stratified analyses to measure the significance of sociodemographic, attitudinal/behavioral, or health status variables. Three studies included covariates from all 3 variable categories. 18,22,25 Thematic analysis of focus group transcripts were presented in the 4 qualitative studies, 1 of which also presented quantitative data.28

The extent of variation in study design makes it difficult to draw strong conclusions across identified studies. Instead, we offer the following observations.

Willingness to Participate in Genetic Research

Studies reported public willingness to participate in genetic research with different measures of consent, including overall consent rates (number providing consent over total sample), responder consent rates (number providing consent over responders), and eligible responder consent rates (number providing consent over eligible responders). The relative merits of each for understanding consent are not discussed explicitly by the authors. However, Royal et al.27 noted that overall consent rates can serve as an indicator of recruitment challenges. In their study, successful enrollment of 43 families into genetic prostate cancer research was the result of more than 8000 initial contacts with potential participants—an overall consent rate of 0.5%. By contrast, the eligible responder consent rate for their study was 75%, providing information about participant willingness during later stages of recruitment.

Overall consent rates varied substantially in the 8 studies that included actual requests for participation, 5 of which had overall consent rates below 40%.18,20,22,23,27 Responder consent rates were substantially higher than overall consent rates, largely because of reduced denominators.18,2123,26,27 The highest responder consent rates had majority White American responders.2123,26 Reported eligible responder consent rates21,23,27 were relatively high ( > 75%). One of these high consent rates resulted from an African American sample.27

Study samples that included people with previous participation in health or genetic research reported overall consent rates ranging from 21% to 85%.17,18,20,22 Studies in which potential participants were provided with specific information about the use of their DNA also had variable consent rates.18,22,23,26,27 Lastly, studies that included people with a personal/familial history of a genetic condition reported lower overall consent rates, ranging from 28% to 53%,20,22,25 the highest resulting from a hypothetical request.25

Variation of Willingness by Racial/Ethnic Group

Statistical tests and multivariate analyses conducted in 6 of the 7 consent studies found racial/ethnic group membership to be a significant predictor of consent. In particular, African American race was a significant predictor of lower levels of consent, with only 1 exception.26

Consent among subjects who had previously participated in health or genetic research varied by racial/ethnic group. Moorman et al.22 found the lowest levels of consent among former research participants. In their study, only 37% of African Americans indicated willingness to enroll in a cancer genetics registry, compared with 58% of White Americans. In addition, exclusive or substantial (41%) African American samples that included people with personal or familial histories of a genetic condition also reported low levels of overall consent (< 37%).20,22

By contrast, Wang et al.25 found that those with a family history of a genetic condition in a largely White American sample reported significantly higher levels of consent. Finally, the highest responder consent rates ( > 85%) resulted from 2 studies with largely White American samples. The first of these 2 studies sampled within a population of older primary care patients18 and the second involved in-home requests for consent.21

Concerns and Opinions About Genetic Research

Opinions about genetic research were presented in 7 studies (Tables 3 [triangle] and 4 [triangle]). Identifying concerns was the primary focus of these studies; however, in 2 studies, the majority of participants reported benefits to genetic research.28,31 Common themes appearing across studies included concerns about discrimination, confidentiality, or the misuse of information, perhaps in part because of a lack of confidence in researchers18,27,30,31; perceived disparities between the participants and beneficiaries of research31; and perceptions of being used by researchers.27 Lack of interest and no perceived benefit from participation were reported in several studies as well.18,26,27 This group of concerns is similar to concerns reported about medical research.3234

More specific to genetic research were several concerns including the potential for those at risk of genetic conditions to be stigmatized and ostracized,29 the initiation of premature treatment,29 changes in familial expectations or interest in “designer babies,”28 and religious objections.28 In the only study that prompted discussion about research on relations among race, genes, and health, Fisher and Wallace29 reported participant skepticism regarding researchers’ abilities to separate genetic, environmental, and racial/ethnic group contributions to health, particularly in cases of mixed heritage. Identified facilitators to participation in genetic research were often reflections of reported concerns (e.g., taking more active control over the use of research by third parties29). Finally, although 5 of the 7 studies in Tables 3 [triangle] and 4 [triangle] included diverse samples, only 1 study compared opinions by racial/ethnic group membership.28

DISCUSSION

We searched for answers to several questions regarding public willingness to participate in and opinions about genetic variation research. We expected to find many more studies given the substantial controversy surrounding its advancement. Only 1 study in our review provided insights into the specific concerns people may have regarding participation in genetic variation research exploring relations among race, genes, and health.

Although there were some patterns by racial/ethnic group membership regarding consent, there were few systematic data across studies that would allow us to draw strong conclusions about the relative willingness of different groups to participate in genetic research.

Recommendations for Future Studies

Following are points for consideration in the design of future studies.

First, it is important to establish clear distinctions in the literature among research studies involving requests for genetic testing, genetic specimen donation, or genetic specimen storage. As discussed previously, the risks and benefits associated with these different requests can vary. Using “genetic research” in reference to all 3 can obscure important distinctions. Using a standard nomenclature when referencing these different requests and corresponding study designs will help ensure that findings regarding consent and public opinion are placed in their appropriate context.

Second, to facilitate cross-study comparisons, future studies must include information needed to calculate overall, responder, and eligible responder consent rates, where applicable. Providing this information by racial/ethnic group membership, other sociodemographic variables, and other characteristics unique to the study (e.g., health, attitudinal/behavior indicators) will facilitate more accurate assessment of consent across studies. Information on the reasons for nonresponse is essential to interpret responder consent rates as well.

Third, researchers conducting qualitative studies should use appropriate probing techniques to identify both the benefits and the concerns participants associate with genetic research. Consent studies should include a qualitative component whereby recruited subjects are asked their reasons for consenting to or declining specific requests. Researchers should build on qualitative findings to measure the extent to which specific or thematic opinions are prevalent in larger diverse samples. When possible, authors should report findings by racial/ethnic group membership.

Fourth, we strongly recommend that future studies explicitly ask potential participants about their willingness to participate in and their opinions regarding genetic variation research, highlighting the exploration of relations among racial/ethnic group membership, genes, and health. Our literature review found only 1 such study. Researchers should make every effort to include Asian Americans, Native Americans, Alaskan Natives, and other groups currently underrepresented.

Finally, to enhance our understanding of how the lay public may perceive genetic variation research, we encourage investigation into parallel areas of research (some of which already appear in the literature11,35,36), including lay public understandings of race, ethnicity, genes, and health and the relations among them; the extent to which people hold views consistent with genetic determinism; and opinions about pharmacogenomics, gene therapy, and other innovations that may arise from genetic research.

Conclusions

Failure to address gaps in this literature will hinder the scientific and ethical advancement of genetic research in general, and genetic variation research in particular. Incomplete data regarding consent may inaccurately portray some groups as less willing to participate in genetic research than others. Furthermore, gaps in information about racial/ethnic group variation in perceived benefits, concerns, and other opinions may delay creative and culturally appropriate strategies to recruit and retain human subjects.

We must open the dialogue occurring within the scientific community about the use of racial/ethic group membership in genetic variation research to members of the general public who may serve as future study participants. As demonstrated by Fisher and Wallace29 and others conducting parallel areas of research, the public can engage in meaningful dialogue about these issues and should be provided with more opportunities to do so.

POSTSCRIPT

During production of this article, 4 new studies satisfying the inclusion criteria for this review came to the authors’ attention via the Centers for Disease Control and Prevention Genomics and Health Weekly Update (http://www.cdc.gov/genomics/update/current.htm).3740 Of note, Buchwald et al.37 reported consent rates for participation in a hypothetical genetic study among 420 urban American Indian/Alaska Native patients and staff at an Indian health care facility. Associations between consent and different study characteristics (i.e., subject matter, risks and benefits, institutional sponsor, community involvement) also were reported.

Acknowledgments

This research was supported in part by the Agency for Healthcare Research and Quality (National Research Service Award Pre-Doctoral Traineeship grant T32-HS000032), the National Human Genome Research Institute, National Institutes of Health (grants R01-HG002830 and P20-HG003387), and the National Center on Minority Health and Health Disparities (grant P60-MD000244).

The authors thank several anonymous reviewers for this journal who provided detailed and thoughtful comments to the article.

Notes

Peer Reviewed

Contributors
G. Corbie-Smith and G. E. Henderson originated the study. R. Sterling led the systematic search and review of relevant literature and led the writing of the article. All authors helped to conceptualize ideas, synthesize findings, propose recommendations, and edit drafts of the article.

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