Anticipated health behaviour changes and perceived control in response to disclosure of genetic risk of breast and ovarian cancer: a quantitative survey study among women in the UK

Rationale and design for a pragmatic randomized trial to assess gene-based prescribing for SSRIs in the treatment of depression

Specific selective serotonin reuptake inhibitors (SSRIs) metabolism is strongly influenced by two pharmacogenes, CYP2D6 and CYP2C19. However, the effectiveness of prospectively using pharmacogenetic variants to select or dose SSRIs for depression is uncertain in routine clinical practice. The objective of this prospective, multicenter, pragmatic randomized controlled trial is to determine the effectiveness of genotype-guided selection and dosing of antidepressants on control of depression in participants who are 8 years or older with ≥3 months of depressive symptoms who require new or revised therapy. Those randomized to the intervention arm undergo pharmacogenetic testing at baseline and receive a pharmacy consult and/or automated clinical decision support intervention based on an actionable phenotype, while those randomized to the control arm have pharmacogenetic testing at the end of 6-months. In both groups, depression and drug tolerability outcomes are assessed at baseline, 1 month, 3 months (primary), and 6 months. The primary end point is defined by change in Patient-Reported Outcomes Measurement Information System (PROMIS) Depression score assessed at 3 months versus baseline. Secondary end points include change inpatient health questionnaire (PHQ-8) measure of depression severity, remission rates defined by PROMIS score < 16, medication adherence, and medication side effects. The primary analysis will compare the PROMIS score difference between trial arms among those with an actionable CYP2D6 or CYP2C19 genetic result or a CYP2D6 drug-drug interaction. The trial has completed accrual of 1461 participants, of which 562 were found to have an actionable phenotype to date, and follow-up will be complete in April of 2024.

Breast Cancer Polygenic-Risk Score Influence on Risk-Reducing Endocrine Therapy Use: Genetic Risk Estimate (GENRE) Trial 1-Year and 2-Year Follow-Up

Refinement of breast cancer risk estimates with a polygenic-risk score (PRS) may improve uptake of risk-reducing endocrine therapy (ET). A previous clinical trial assessed the influence of adding a PRS to traditional risk estimates on ET use. We stratified participants according to PRS-refined breast cancer risk and evaluated ET use and ET-related quality of life (QOL) at 1-year (previously reported) and 2-year follow-ups. Of 151 participants, 58 (38.4%) initiated ET, and 22 (14.6%) discontinued ET by 2 years; 42 (27.8%) and 36 (23.8%) participants were using ET at 1- and 2-year follow-ups, respectively. At the 2-year follow-up, 39% of participants with a lifetime breast cancer risk of 40.1% to 100.0%, 18% with a 20.1% to 40.0% risk, and 16% with a 0.0% to 20.0% risk were taking ET (overall P = 0.01). Moreover, 40% of participants whose breast cancer risk increased by 10% or greater with addition of the PRS to a traditional breast cancer-risk model were taking ET versus 0% whose risk decreased by 10% or greater (P = 0.004). QOL was similar for participants taking or not taking ET at 1- and 2-year follow-ups, although most who discontinued ET did so because of adverse effects. However, these QOL results may have been skewed by the long interval between QOL surveys and lack of baseline QOL data. PRS-informed breast cancer prevention counseling has a lasting, but waning, effect over time. Additional follow-up studies are needed to address the effect of PRS on ET adherence, ET-related QOL, supplemental breast cancer screening, and other risk-reducing behaviors.

PREVENTION RELEVANCE

Risk-reducing medications for breast cancer are considerably underused. Informing women at risk with precise and individualized risk assessment tools may substantially affect the incidence of breast cancer. In our study, a risk assessment tool (IBIS-polygenic-risk score) yielded promising results, with 39% of women at highest risk starting preventive medication.

The Views of Patients with Isolated Rapid Eye Movement Sleep Behavior Disorder on Risk Disclosure

BACKGROUND

Isolated rapid eye movement sleep behavior disorder (iRBD) is associated with an increased risk of Parkinson's disease and other synucleinopathies. There is no consensus about disclosure of this risk to patients with iRBD.

OBJECTIVE

The objective of our study was to assess the experiences of risk disclosure in a group of patients with iRBD and their views on what, when, and how this should be done.

METHODS

A survey was administered to patients with iRBD to explore their experiences and views on risk disclosure.

RESULTS

Thirty-one patients with iRBD (28 males; mean age, 70 [SD 8.7] years; mean disease duration, 8.7 [SD 6.4] years) were included. A third reported they had not been informed about the link between iRBD and other conditions by clinicians at diagnosis, but 90% would have liked to have received prognostic information, and 60% indicated that this should happen at the point that iRBD was diagnosed. Most participants wanted this information to come from the clinician diagnosing and treating iRBD (90.3%). Almost three-quarters (72.2%) had searched for this information online.

CONCLUSIONS

Patients with iRBD mostly wished to have received information regarding the potential implications of iRBD when the diagnosis was made. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

A mainstreaming oncogenomics model: improving the identification of Lynch syndrome

Introduction

"Mainstreaming" is a proposed strategy to integrate genomic testing into oncology. The aim of this paper is to develop a mainstreaming oncogenomics model by identifying health system interventions and implementation strategies for mainstreaming Lynch syndrome genomic testing.

Methods

A rigorous theoretical approach inclusive of conducting a systematic review and qualitative and quantitative studies was undertaken using the Consolidated Framework for Implementation Research. Theory-informed implementation data were mapped to the Genomic Medicine Integrative Research framework to generate potential strategies.

Results

The systematic review identified a lack of theory-guided health system interventions and evaluation for Lynch syndrome and other mainstreaming programs. The qualitative study phase included 22 participants from 12 health organizations. The quantitative Lynch syndrome survey included 198 responses: 26% and 66% from genetic and oncology health professionals, respectively. Studies identified the relative advantage and clinical utility of mainstreaming to improve genetic test access and to streamline care, and adaptation of current processes was recognized for results delivery and follow-up. Barriers identified included funding, infrastructure and resources, and the need for process and role delineation. The interventions to overcome barriers were as follows: embedded mainstream genetic counselors, electronic medical record genetic test ordering, results tracking, and mainstreaming education resources. Implementation evidence was connected through the Genomic Medicine Integrative Research framework resulting in a mainstreaming oncogenomics model.

Discussion

The proposed mainstreaming oncogenomics model acts as a complex intervention. It features an adaptable suite of implementation strategies to inform Lynch syndrome and other hereditary cancer service delivery. Implementation and evaluation of the model are required in future research.

Randomised trial of population-based BRCA testing in Ashkenazi Jews: long-term secondary lifestyle behavioural outcomes

OBJECTIVE

Ashkenazi-Jewish (AJ) population-based BRCA testing is acceptable, cost-effective and amplifies primary prevention for breast & ovarian cancer. However, data describing lifestyle impact are lacking. We report long-term results of population-based BRCA testing on lifestyle behaviour and cancer risk perception.

DESIGN

Two-arm randomised controlled trials (ISRCTN73338115, GCaPPS): (a) population-screening (PS); (b) family history (FH)/clinical criteria testing.

SETTING

North London AJ-population.

POPULATION/SAMPLE

AJ women/men >18 years.

EXCLUSIONS

prior BRCA testing or first-degree relatives of BRCA-carriers.

METHODS

Participants were recruited through self-referral. All participants received informed pre-test genetic counselling. The intervention included genetic testing for three AJ BRCA-mutations: 185delAG(c.68_69delAG), 5382insC(c.5266dupC) and 6174delT(c.5946delT). This was undertaken for all participants in the PS arm and participants fulfilling FH/clinical criteria in the FH arm. Patients filled out customised/validated questionnaires at baseline/1-year/2-year/3-year follow-ups. Generalised linear-mixed models adjusted for covariates and appropriate contrast tests were used for between-group/within-group analysis of lifestyle and behavioural outcomes along with evaluating factors associated with these outcomes. Outcomes are adjusted for multiple testing (Bonferroni method), with P < 0.0039 considered significant.

OUTCOME MEASURES

Lifestyle/behavioural outcomes at baseline/1-year/2-year/3-year follow-ups.

RESULTS

1034 participants were randomised to PS (n = 530) or FH (n = 504) arms. No significant difference was identified between PS- and FH-based BRCA testing approaches in terms of dietary fruit/vegetable/meat consumption, vitamin intake, alcohol quantity/ frequency, smoking behaviour (frequency/cessation), physical activity/exercise or routine breast mammogram screening behaviour, with outcomes not affected by BRCA test result. Cancer risk perception decreased with time following BRCA testing, with no difference between FH/PS approaches, and the perception of risk was lowest in BRCA-negative participants. Men consumed fewer fruits/vegetables/vitamins and more meat/alcohol than women (P < 0.001).

CONCLUSION

Population-based and FH-based AJ BRCA testing have similar long-term lifestyle impacts on smoking, alcohol, dietary fruit/vegetable/meat/vitamin, exercise, breast screening participation and reduced cancer risk perception.

Unselected Population Genetic Testing for Personalised Ovarian Cancer Risk Prediction: A Qualitative Study Using Semi-Structured Interviews

Unselected population-based personalised ovarian cancer (OC) risk assessments combining genetic, epidemiological and hormonal data have not previously been undertaken. We aimed to understand the attitudes, experiences and impact on the emotional well-being of women from the general population who underwent unselected population genetic testing (PGT) for personalised OC risk prediction and who received low-risk (<5% lifetime risk) results. This qualitative study was set within recruitment to a pilot PGT study using an OC risk tool and telephone helpline. OC-unaffected women ≥ 18 years and with no prior OC gene testing were ascertained through primary care in London. In-depth, semi-structured and 1:1 interviews were conducted until informational saturation was reached following nine interviews. Six interconnected themes emerged: health beliefs; decision making; factors influencing acceptability; effect on well-being; results communication; satisfaction. Satisfaction with testing was high and none expressed regret. All felt the telephone helpline was helpful and should remain optional. Delivery of low-risk results reduced anxiety. However, care must be taken to emphasise that low risk does not equal no risk. The main facilitators were ease of testing, learning about children’s risk and a desire to prevent disease. Barriers included change in family dynamics, insurance, stigmatisation and personality traits associated with stress/worry. PGT for personalised OC risk prediction in women in the general population had high acceptability/satisfaction and reduced anxiety in low-risk individuals. Facilitators/barriers observed were similar to those reported with genetic testing from high-risk cancer clinics and unselected PGT in the Jewish population.

Predictors of cardiopulmonary fitness in cancer-affected and -unaffected women with a pathogenic germline variant in the genes BRCA1/2 (LIBRE-1)

Physical activity (PA) helps prevention and aftercare of sporadic breast cancer (BC), cardiopulmonary fitness (CPF) being an age-independent predictor of tumor-specific mortality. Therefore, we wanted to identify predictors of CPF (represented by peak oxygen uptake: VO_2peak) in BRCA1/2 mutation carriers whose risk of developing BC is high. We used cross-sectional data from 68 BRCA1/2 germline mutation carrying women participating in the randomized, prospective, controlled clinical study LIBRE-1. Assessments included cardiopulmonary exercise testing, medical and lifestyle history plus socioeconomic status. Additionally, the participants completed a psychological questionnaire regarding their attitude, subjective norms, perceived behavior control and intention towards PA. A multivariate logistic regression model was used to identify predictors for participants reaching their age- and sex-adjusted VO_2peak reference values. 22 participants (median age: 40 years, interquartile range (IQR) 33–46) were cancer-unaffected and 46 cancer-affected (median age: 44 years, IQR 35–50). The strongest predictor for reaching the reference VO_2peak value was attitude towards PA (Odds Ratio 3.0; 95% Confidence Interval 1.3–8.4; p = 0.021). None of the other predictors showed a significant association. A positive attitude towards PA seems to be associated with VO_2peak, which should be considered in developing therapeutic and preventive strategies.

Trial registrations: NCT02087592; DRKS00005736.

Information needs on breast cancer genetic and non-genetic risk factors in relatives of women with a BRCA1/2 or PALB2 pathogenic variant

OBJECTIVES

Comprehensive breast cancer (BC) risk models integrating effects of genetic (GRF) and non-genetic risk factors (NGRF) may refine BC prevention recommendations. We explored the perceived information received on BC risk factors, and related characteristics, in female relatives of women with a BRCA1/2 or PALB2 pathogenic variant, undergoing BC risk assessment using the CanRisk© prediction tool.

METHODS

Of 200 consecutive cancer-free women approached after the initial genetic consultation, 161 (80.5%) filled in questionnaires on their perception of information received and wished further information on BC risk factors (e.g., being a carrier of a moderate risk altered gene, personal genetic profile, lifestyles). Multilevel multivariate linear models were performed accounting for the clinician who met the counselee and exploring the effect of counselees' socio-demographic, familial and psychological characteristics on the perceived extent of information received.

RESULTS

Perceived no/little information received and wish for further information were more frequent for NGRF (>50%) than for GRF, especially high-risk genes (<20%). Perceived amount of information received and desire for further information were inversely correlated (p=<0.0001). Higher education level related to lower perceived levels of information received on GRF. Younger counselees' age (β = 0.13, p = 0.02) and less frequent engagement coping (e.g., inclination to solicit information) (β = 0.24, p = 0.02) related to lower perceived information received about NGRF. Other assessed counselees' features were not found to be associated to GRF and NGRF information perception.

CONCLUSIONS

Awareness of counselees' perceived lack of information on BC risk factors indicates a need to enhance evidence-based information on BC NGRF especially.

Disclosing Pharmacogenetic Feedback of Caffeine via eHealth Channels, Assessment of the Methods and Effects to Behavior Change: A Pilot Study

Background: The integration of genetic testing into eHealth applications holds great promise for the personalization of disease prevention guidelines. However, relatively little is known about the impact of eHealth applications on an individual's behavior. Aim: The aim of the pilot study was to investigate the effect of the personalized eHealth application approach to behavior change in a 1-month follow-up period on groups with previously known and unknown caffeine impacts. Method: We created a direct-to-consumer approach that includes providing relevant information and personalized reminders and goals on the digital device regarding the caffeine intake for two groups of individuals: the intervention group (IG) with the genetic raw data available and the control group (CG) to test the impact of the same content (article about caffeine metabolism) on participants without the genetic test. Study participants were all Estonians (n = 160). Results: The study suggests that eHealth applications work for short-term behavior change. Participants in the genetic IG tended to increase caffeine intake if they were informed about caffeine not being harmful. They reported feeling better physically and/or mentally after their behavioral change decision during the period of the study. Conclusions: Our pilot study revealed that eHealth applications may have a positive effect for short-term behavior change, regardless of a prior genetic test. Further studies among larger study groups are required to achieve a better understanding about behavior change of individuals in the field of personalized medicine and eHealth interventions.

Implementation and implications for polygenic risk scores in healthcare

Increasing amounts of genetic data have led to the development of polygenic risk scores (PRSs) for a variety of diseases. These scores, built from the summary statistics of genome-wide association studies (GWASs), are able to stratify individuals based on their genetic risk of developing various common diseases and could potentially be used to optimize the use of screening and preventative treatments and improve personalized care for patients. Many challenges are yet to be overcome, including PRS validation, healthcare professional and patient education, and healthcare systems integration. Ethical challenges are also present in how this information is used and the current lack of diverse populations with PRSs available. In this review, we discuss the topics above and cover the nature of PRSs, visualization schemes, and how PRSs can be improved. With these tools on the horizon for multiple diseases, scientists, clinicians, health systems, regulatory bodies, and the public should discuss the uses, benefits, and potential risks of PRSs.

Intrafamilial communication of hereditary breast and ovarian cancer genetic information in Italian women: towards a personalised approach

Genomic testing expansion is accompanied by an increasing need for genetic counselling and intrafamilial communication. Genetic counselling can play an important role in facilitating intrafamilial communication and relationships. We conducted a cross-sectional, multicenter study including 252 Italian women, using a questionnaire divided in two sections, the first one to be filled after the pre-test counselling and the second after receiving BRCA test results. We assessed the factors influencing intrafamilial disclosure of genetic information for hereditary breast and ovarian cancer, family members with whom probands are more prone to share genetic information, and the perceived understanding of information received by counselees during genetic counselling. Women were accompanied to the counselling more often by their husband/partner. Among those with a positive BRCA test result, 49% intended to communicate it to their offspring and 27% to their husband/partner. Younger women, those living with their husband/partner, and those who described family communication as open/profound and spontaneous/sincere had a higher probability of being accompanied during genetic counselling and discuss about it with relatives. Spontaneous/sincere or open/profound family communication and joyful/happy familial relationships were associated with the decision to undergo genetic testing as a responsibility towards relatives. Women had a good understanding of counselling contents (mean score 9.27 in a scale 1-10). Genetic counselling providers should consider that genetic information disclosure does not depend only on the clarity of the information provided, but also on pre-existing intrafamilial communication and relationships, family structure and marital status, indicating the need for a personalised approach accounting for these factors.

Risk factor analysis combined with deep learning in the risk assessment of overseas investment of enterprises

To evaluate the overseas investment risks of enterprises and expand the application and development of deep learning methods in risk assessment, 15 national clusters are utilized as samples to analyze and discuss the overseas investment risk indicators of enterprises. First, based on the indicator system of overseas investment risks, five major types of investment risks are identified. Second, the Deep Neural Network (DNN) is introduced; a risk evaluation model is constructed for enterprise overseas investment. Finally, the investment attractiveness index in the Fraser risk assessment learning label is adopted as the evaluation results of the model. According to the classification of risks, the model is trained and its performance is tested. The results show that the major source of overseas investment risks includes basic resources, political systems, economic and financial development, and environmental protection. The corresponding risk score is high. North American country clusters and Oceanian country clusters have lower investment risks, while the investment risks in Africa, Latin America, and Asia are affected by multiple factors of the specific cities. This is closely related to the resources and legal systems possessed by the country clusters. This is of great significance for enterprises to conduct risk assessment in overseas investment.

A systematic review of communication interventions to help healthcare professionals discuss genetic testing for breast cancer

Purpose

This systematic review examined educational training interventions for healthcare professionals (HCPs) discussing genetic testing and risk for hereditary breast cancer. There was a particular focus on the presence, and content, of communication elements within these packages.

Methods

Searches were run via CINAHL, EMBASE, PUBMED, and PsychInfo in February 2019 to identify training interventions available to HCPs with reference to communication skills. Studies were assessed for quality, with relevant intervention and outcome data extracted and synthesized. This review followed the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) statement and was registered on the PROSPERO database (CRD42019124010).

Results

Of 3,988 items, seven papers, two of which were linked, were eligible for inclusion. There was a mix of randomized and single arm studies with web-based and face-to-face interventions. Content included an overview of genetics, hereditary and familial background, and recommended practice techniques. Outcomes focused on communication, self-efficacy, knowledge, and satisfaction. Interventions were designed for genetic counselors, physicians, primary care physicians (PCPs), medical students, and nurses. None of the papers featured oncologists or surgeons.

Conclusions

This review revealed an overall lack of publications which evaluated interventions to assist HCPs discussing hereditary breast cancer risk and testing. Studies failed to operationalize which ‘communication skills’ they included, nor did they consistently report randomization, outcome measures, or analysis.

Discussing the need for, and management of, genetic testing for inherited cancer risk with individuals and their families can be challenging. As genetic testing in breast cancer becomes more common, the provision of specific communication-based training programs, with reference to genetic testing, risk assessments, and counseling skills is warranted.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05741-z) contains supplementary material, which is available to authorized users.

Population-based Genetic Testing for Precision Prevention

Global interest in genetic testing for cancer susceptibility genes (CSG) has surged with falling costs, increasing awareness, and celebrity endorsement. Current access to genetic testing is based on clinical criteria/risk model assessment which uses family history as a surrogate. However, this approach is fraught with inequality, massive underutilization, and misses 50% CSG carriers. This reflects huge missed opportunities for precision prevention. Early CSG identification enables uptake of risk-reducing strategies in unaffected individuals to reduce cancer risk. Population-based genetic testing (PGT) can overcome limitations of clinical criteria/family history-based testing. Jewish population studies show population-based BRCA testing is feasible, acceptable, has high satisfaction, does not harm psychologic well-being/quality of life, and is extremely cost-effective, arguing for changing paradigm to PGT in the Jewish population. Innovative approaches for delivering pretest information/education are needed to facilitate informed decision-making for PGT. Different health systems will need context-specific implementation strategies and management pathways, while maintaining principles of population screening. Data on general population PGT are beginning to emerge, prompting evaluation of wider implementation. Sophisticated risk prediction models incorporating genetic and nongenetic data are being used to stratify populations for ovarian cancer and breast cancer risk and risk-adapted screening/prevention. PGT is potentially cost-effective for panel testing of breast and ovarian CSGs and for risk-adapted breast cancer screening. Further research/implementation studies evaluating the impact, clinical efficacy, psychologic and socio-ethical consequences, and cost-effectiveness of PGT are needed.

Population Study of Ovarian Cancer Risk Prediction for Targeted Screening and Prevention

Unselected population-based personalised ovarian cancer (OC) risk assessment combining genetic/epidemiology/hormonal data has not previously been undertaken. We aimed to perform a feasibility study of OC risk stratification of general population women using a personalised OC risk tool followed by risk management. Volunteers were recruited through London primary care networks.

INCLUSION CRITERIA

women ≥18 years.

EXCLUSION CRITERIA

prior ovarian/tubal/peritoneal cancer, previous genetic testing for OC genes. Participants accessed an online/web-based decision aid along with optional telephone helpline use. Consenting individuals completed risk assessment and underwent genetic testing (BRCA1/BRCA2/RAD51C/RAD51D/BRIP1, OC susceptibility single-nucleotide polymorphisms). A validated OC risk prediction algorithm provided a personalised OC risk estimate using genetic/lifestyle/hormonal OC risk factors. Population genetic testing (PGT)/OC risk stratification uptake/acceptability, satisfaction, decision aid/telephone helpline use, psychological health and quality of life were assessed using validated/customised questionnaires over six months. Linear-mixed models/contrast tests analysed impact on study outcomes.

MAIN OUTCOMES

feasibility/acceptability, uptake, decision aid/telephone helpline use, satisfaction/regret, and impact on psychological health/quality of life. In total, 123 volunteers (mean age = 48.5 (SD = 15.4) years) used the decision aid, 105 (85%) consented. None fulfilled NHS genetic testing clinical criteria. OC risk stratification revealed 1/103 at ≥10% (high), 0/103 at ≥5%-<10% (intermediate), and 100/103 at <5% (low) lifetime OC risk. Decision aid satisfaction was 92.2%. The telephone helpline use rate was 13% and the questionnaire response rate at six months was 75%. Contrast tests indicated that overall depression (p = 0.30), anxiety (p = 0.10), quality-of-life (p = 0.99), and distress (p = 0.25) levels did not jointly change, while OC worry (p = 0.021) and general cancer risk perception (p = 0.015) decreased over six months. In total, 85.5-98.7% were satisfied with their decision. Findings suggest population-based personalised OC risk stratification is feasible and acceptable, has high satisfaction, reduces cancer worry/risk perception, and does not negatively impact psychological health/quality of life.

The accuracy of depression risk perception in high risk Canadians

BACKGROUND

Prevention and early detection of depression is a top public health priority. Accurate perception of depression risk may play an important role in health behavior change and prevention of depression. However, the way in which people in the community perceive their risk of developing depression is currently unknown.

METHODS

We analyzed the baseline data from a randomized controlled trial in 358 men and 356 women who are at high risk of having a major depressive episode (MDE). The predicted risk was assessed by sex-specific multivariable risk predictive algorithms for MDE. We compared participants' perceived risk and their predicted risk. Accurate risk perception was defined as perceived risk is in the range of predicted risk ± 10%.

RESULTS

In men, 29.7% perceived their risk accurately; 47.5% overestimated their risk; 22.8% underestimated their risk. In women, the proportions were 21.7%, 59.6% and 18.7%, respectively. Compared to men, women were more likely to overestimate their risk and less likely to be accurate. Regression modeling revealed that poor self-rated health and higher predicted depression risk were associated with inaccuracy of risk perception in men; a family history of MDE, higher psychological distress and lower predicted risk were associated with inaccuracy of risk perception in women.

CONCLUSIONS

Individuals who are at high risk of developing depression tend to overestimate their risk, especially women. Inaccurate depression risk perception is related to people's health status. Educational interventions are needed to enhance the accuracy of risk perception to encourage positive behavior change and uptake of preventive strategies.

Population Based Testing for Primary Prevention: A Systematic Review

The current clinical model for genetic testing is based on clinical-criteria/family-history (FH) and a pre-defined mutation probability threshold. It requires people to develop cancer before identifying unaffected individuals in the family to target prevention. This process is inefficient, resource intensive and misses >50% of individuals or mutation carriers at risk. Population genetic-testing can overcome these limitations. It is technically feasible to test populations on a large scale; genetic-testing costs are falling and acceptability and awareness are rising. MEDLINE, EMBASE, Pubmed, CINAHL and PsychINFO databases were searched using free-text and MeSH terms; retrieved reference lists of publications were screened; additionally, web-based platforms, Google, and clinical-trial registries were searched. Quality of studies was evaluated using appropriate check-lists. A number of studies have evaluated population-based BRCA-testing in the Jewish population. This has been found to be acceptable, feasible, clinically-effective, safe, associated with high satisfaction rates and extremely cost-effective. Data support change in guidelines for population-based BRCA-testing in the Jewish population. Population panel testing for BRCA1/BRCA2/RAD51C/RAD51D/BRIP1/PALB2 gene mutations is the most cost-effective genetic-testing strategy in general-population women and can prevent thousands more breast and ovarian cancers than current clinical-criteria based approaches. A few ongoing studies are evaluating population-based genetic-testing for multiple cancer susceptibility genes in the general population but more implementation studies are needed. A future population-testing programme could also target other chronic diseases.