Opinion shifts on human germline gene editing as a result of the Dutch DNA Dialogue Project
Study design and participants
Participants were included between August 2019 and January 2021. First, a public opinion poll with two independent samples of the Dutch population aimed to show national opinions and changes in opinion over the duration of the dialogue project DNA. Although we were unable to link these changes to specific events, we were interested in general trends in the complex system of opinion development on the HGGE. In the event of a major event that changes the opinion of Dutch citizens as a whole, these samples could also serve as reference samples for those at the dialogue level. The first sample (S1) was recruited in August 2019, before the start of the project. The second sample (S2) was recruited in April 2020, when most physical dialogue had taken place and further progress became uncertain due to the Covid-19 pandemic. Second, the repeated cross-sectional approach included independent responses from a first sample (S3) of people who registered to participate in the dialogue or showed an interest in the project, and a second sample (S4) of people who had participated to one of the 27 dialogue meetings or a spin-off dialogue. Given the difficulty of getting people to complete two questionnaires, before and after the dialogue, we decided to include these cross-sectional samples in our analyzes while controlling for confounders. In this way, the cross-sectional approach always provides an indication of the change in opinion as a result of participation in the dialogue. Third, the deliberative poll included a unique sample (S5) of participants who completed our questionnaire both before and after participating in a dialogue meeting. Participants in S4 and S5 visited one of the 15/27 dialogues or a derived dialogue.
Participants for the deliberative survey and the repeated cross-sectional survey were recruited by email either through an intermediary in the organization (e.g., a teacher in a high school or a representative of a patient organization), or they could indicate their interest. to participate by leaving their email address when registering for a DNA dialogue meeting. Registration for the questionnaire was also available on the DNA Dialogue website and participants could scan a QR code linking to the questionnaire on-site at several DNA Dialogue meetings. Public opinion survey participants were recruited through the business research firm Motivaction. Motivaction distributed the questionnaire to members of its StemPunt research panel (ISO certified; www.motivaction.nl/panel-stempunt). We included approximately 1200 participants in each sample (S1 and S2). Participants had to be between the ages of 18 and 75, and panel members who had participated in S1 were excluded from being invited to S2. To reduce selection bias, Motivaction used regression analysis to determine propensity scores expressing deviations of their panel from the Dutch population on gender, age, education level, region, lifestyle and value measures, and the interactions between these characteristics. To determine these deviations, the Golden Standard from Statistics Netherlands and the (bi-)annual lifestyle and value measures from Motivaction were used as a reference. . Underrepresented groups received a higher propensity score, increasing the chances of being selected. In the cleaned samples (S1 and S2), the remaining deviations from the Dutch population were flagged, allowing the data to be weighted to correct for these deviations. To avoid further selection bias, the invitations to participate did not reveal any information about the content of the questionnaire. Active panel members receive points for each survey they complete, which can be redeemed for gift cards or charitable donations. Motivaction acts in accordance with the General Data Protection Regulation. StemPunt Research Panel is registered with the Dutch Data Protection Authority. Exclusion criteria for all samples can be found in Table 1 and are detailed in Supplementary Material.
This study focuses on a selection of questions, the full questionnaire (in Dutch) can be found elsewhere (see supplementary material for link). For all participants (S1–5), the questionnaire included questions about demographic characteristics, acceptance of various applications of HGGE, and a question about participants’ opinions.
The demographic characteristics we present here have already been studied with regard to the acceptability of gene therapy . Education level categories – high, middle and low – were determined according to the standard of the Central Bureau of Statistics .
The ac questions below measured agreement with HGGE’s apps on a 5-point scale (1 = Strongly Disagree, 2 = Disagree, 3 = Neutral, 4 = Agree, 5 = Strongly Agree) . Participants indicated the extent to which they agreed with modifying the DNA of an embryo in these scenarios:
(a) “Someone who wants to have a child has a serious hereditary muscle disease. For a future pregnancy, doctors can alter the DNA of an embryo to prevent the child from inheriting the serious muscle disease. Assume the technology is safe and effective.
(b) “Someone who wishes to have a child is in good health. For a future pregnancy, doctors can modify the DNA of an embryo to protect the child against serious infectious diseases, such as HIV. Assume the technology is safe and effective.
(c) “Someone who wishes to have a child is in good health. For a future pregnancy, doctors can modify the DNA of an embryo, in order to increase the intelligence of the child. Assume the technology is safe and effective.
Respondents were asked to describe their thoughts on the DNA modification of embryos in max. three key words. Responses were grouped and categorized, resulting in five opinion clusters: positive, negative, mixed (positive and negative), descriptive (positive or negative), or indeterminable (no opinion expressed, e.g. opinion”, “?”, or “-“. Two researchers (BV and DH) coded the responses independently, with good interrater reliability (κ= 0.80, p
Impact of participation
S4 and S5 participants were asked how their visit to a DNA dialogue meeting changed their perspective on HGGE.
The local Medical Ethics Committee (METC) exempted this study from the Medical Research Involving Human Subjects (WMO) Act (number: MEC-2019-0368).
Descriptive analyzes were used for demographic characteristics, acceptance rates ((strongly) disagree, neutral, (strongly) agree) and categorized opinion rates (positive, negative, mixed, descriptive, undeterminable) . Demographic characteristics were compared (S1–S2 and S3–S4) using chi-square tests (Fisher’s exact tests when assumptions were not met). Propensity weighting as specified above was used on the most recent public opinion poll sample (S2) to derive population estimates of acceptance and opinion. To assess changes in acceptance rates, public opinion surveys and repeated cross-sectional acceptance data (scale 1–5) were compared (S1–S2 and S3–S4) using you-tests, while data from deliberative polls (S5) were compared using you-tests. To compare categorized opinions, dummy variables were created (e.g. positive yes = 1, no = 0) and chi-square tests (Fisher’s exact tests when assumptions were not met) were used for independent samples (S1–S2 and S3–S4) and McNemar’s tests for paired samples (S5). Because repeated cross-sectional measures are subject to internal validity threats, analyzes with adjusted samples were performed to exclude confounding demographic characteristics. Finally, the self-reported impact of participating in the dialogue on HGGE’s outlook was analyzed using thematic analysis. Initial themes were identified and coded by DH and then verified by BV. IBM SPSS Statistics version 25.0 was used for data analyzes and the level of significance was set at 0.05, two-sided.