Parkinson's disease variant detection and disclosure: PD GENEration, a North American study.

Variants in seven genes (LRRK2, GBA1, PRKN, SNCA, PINK1, PARK7 and VPS35) have been formally adjudicated as causal contributors to Parkinson's disease; however, individuals with Parkinson's disease are often unaware of their genetic status since clinical testing is infrequently offered. As a result, genetic information is not incorporated into clinical care, and variant-targeted precision medicine trials struggle to enrol people with Parkinson's disease. Understanding the yield of genetic testing using an established gene panel in a large, geographically diverse North American population would help patients, clinicians, clinical researchers, laboratories and insurers better understand the importance of genetics in approaching Parkinson's disease. PD GENEration is an ongoing multi-centre, observational study (NCT04057794, NCT04994015) offering genetic testing with results disclosure and genetic counselling to those in the US (including Puerto Rico), Canada and the Dominican Republic, through local clinical sites or remotely through self-enrolment. DNA samples are analysed by next-generation sequencing including deletion/duplication analysis (Fulgent Genetics) with targeted testing of seven major Parkinson's disease-related genes. Variants classified as pathogenic/likely pathogenic/risk variants are disclosed to all tested participants by either neurologists or genetic counsellors. Demographic and clinical features are collected at baseline visits. Between September 2019 and June 2023, the study enrolled 10 510 participants across >85 centres, with 8301 having received results. Participants were: 59% male; 86% White, 2% Asian, 4% Black/African American, 9% Hispanic/Latino; mean age 67.4 ± 10.8 years. Reportable genetic variants were observed in 13% of all participants, including 18% of participants with one or more 'high risk factors' for a genetic aetiology: early onset (<50 years), high-risk ancestry (Ashkenazi Jewish/Basque/North African Berber), an affected first-degree relative; and, importantly, in 9.1% of people with none of these risk factors. Reportable variants in GBA1 were identified in 7.7% of all participants; 2.4% in LRRK2; 2.1% in PRKN; 0.1% in SNCA; and 0.2% in PINK1, PARK7 or VPS35 combined. Variants in more than one of the seven genes were identified in 0.4% of participants. Approximately 13% of study participants had a reportable genetic variant, with a 9% yield in people with no high-risk factors. This supports the promotion of universal access to genetic testing for Parkinson's disease, as well as therapeutic trials for GBA1 and LRRK2-related Parkinson's disease.

Providing genetic testing and genetic counseling for Parkinson's disease to the community.

PURPOSE: To evaluate the feasibility and impact of offering genetic testing and counseling to patients with Parkinson's disease (PD), with the potential to enroll in gene-targeted clinical trials and improve clinical care. METHODS: A multicenter, exploratory pilot study at 7 academic hospital sites in the United States tracked enrollment and randomized participants to receive results and genetic counseling at local sites or by genetic counselors, remotely. Follow-up surveys measured participant/provider satisfaction, knowledge, and psychological impact. RESULTS: From September 5, 2019 to January 4, 2021, 620 participants were enrolled and 387 completed outcome surveys. There were no significant differences in outcomes between local and remote sites, with both arms reporting high knowledge and satisfaction scores (>80%). Notably, 16% of those tested had reportable PD gene variants (pathogenic/likely pathogenic/risk allele). CONCLUSION: Local clinicians, as well as genetic counselors, with educational support as needed, can effectively return genetic results for PD as we observed favorable outcome measures in both groups. Increasing access to PD genetic testing and counseling is urgent; this can inform future efforts to integrate genetic testing and counseling into clinical care for all those with PD.

Genetic Testing in Parkinson's Disease.

Genetic testing for persons with Parkinson's disease is becoming increasingly common. Significant gains have been made regarding genetic testing methods, and testing is becoming more readily available in clinical, research, and direct-to-consumer settings. Although the potential utility of clinical testing is expanding, there are currently no proven gene-targeted therapies, but clinical trials are underway. Furthermore, genetic testing practices vary widely, as do knowledge and attitudes of relevant stakeholders. The specter of testing mandates financial, ethical, and physician engagement, and there is a need for guidelines to help navigate the myriad of challenges. However, to develop guidelines, gaps and controversies need to be clearly identified and analyzed. To this end, we first reviewed recent literature and subsequently identified gaps and controversies, some of which were partially addressed in the literature, but many of which are not well delineated or researched. Key gaps and controversies include: (1) Is genetic testing appropriate in symptomatic and asymptomatic individuals without medical actionability? (2) How, if at all, should testing vary based on ethnicity? (3) What are the long-term outcomes of consumer- and research-based genetic testing in presymptomatic PD? (4) What resources are needed for clinical genetic testing, and how is this impacted by models of care and cost-benefit considerations? Addressing these issues will help facilitate the development of consensus and guidelines regarding the approach and access to genetic testing and counseling. This is also needed to guide a multidisciplinary approach that accounts for cultural, geographic, and socioeconomic factors in developing testing guidelines. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

International Genetic Testing and Counseling Practices for Parkinson's Disease.

BACKGROUND: There is growing clinical and research utilization of genetic testing in Parkinson's disease (PD), including direct-to-consumer testing. OBJECTIVES: The aim is to determine the international landscape of genetic testing in PD to inform future worldwide recommendations. METHODS: A web-based survey assessing current practices, concerns, and barriers to genetic testing and counseling was administered to the International Parkinson and Movement Disorders Society membership. RESULTS: Common hurdles across sites included cost and access to genetic testing, and counseling, as well as education on genetic counseling. Region-dependent differences in access to and availability of testing and counseling were most notable in Africa. High-income countries also demonstrated heterogeneity, with European nations more likely to have genetic testing covered through insurance than Pan-American and Asian countries. CONCLUSIONS: This survey highlights not only diversity of barriers in different regions but also the shared and highly actionable needs for improved education and access to genetic counseling and testing for PD worldwide. © 2023 International Parkinson and Movement Disorder Society.

The Role of Genetic Testing for Parkinson's Disease.

PURPOSE OF REVIEW: To describe current practices and attitudes about genetic testing for Parkinson's disease (PD) among neurologists, highlight the changing scene of genetic testing for PD, and provide guidance on facilitating PD genetic testing in a clinical practice. RECENT FINDINGS: Since the 1990s, researchers have discovered several major gene variants contributing to PD etiology. A large body of literature now exists supporting the frequency of these variants in different populations and their effects on phenotype and clinical course. Recently, clinical trials have emerged with therapies targeting genetic forms of PD, specifically LRRK2 and GBA. Despite this growing knowledge, genetic testing for PD is not typically offered by neurologists including movement disorder specialists. Neurologists express concerns about the financial and practical issues of genetic testing as well as the potential impact on their patients. Researchers and specialists in the field are questioning this hesitation as clinical utility and consumer demand increase. Consideration of genetic testing for PD is shifting, as we enter a new era of precision medicine and gain clinical knowledge about PD. Barriers to testing, as perceived by clinicians, can be overcome with education, support, and involvement of multiple stakeholders with the goal of making PD genetic testing accessible to all patients.

Outcomes of genetic test disclosure and genetic counseling in a large Parkinson's disease research study.

Genetic testing for Parkinson's disease (PD) is growing as interventional clinical trials begin to enroll participants with PD who carry pathogenic variants in the LRRK2 or GBA genes. However, the impact of receiving genetic test results and the satisfaction with receiving genetic counseling among PD populations have not yet been studied. The purpose of this study was to evaluate (1) the psychological impact of genetic testing for PD and (2) satisfaction with genetic counseling. Surveyed participants (N = 875) were individuals with PD or at risk of developing PD, initially recruited for the Parkinson's Progression Marker Initiative (PPMI) study and currently enrolled in the Widespread Recruitment Initiative (WRI) at Indiana University. Individuals were surveyed following genetic test disclosure and genetic counseling regarding results from targeted testing for pathogenic variants in the LRRK2 and GBA genes. Participants were surveyed via two tools: a modified version of the Multidimensional Impact of Cancer Risk Assessment Survey (M-MICRA), which measured the psychological impact of genetic testing and the Genetic Counseling Satisfaction Survey (GCSS). Participants were divided into affected/unaffected and variant positive/negative groups for subset analyses. The majority of participants had favorable M-MICRA scores and were satisfied with the disclosure of the genetic test results and genetic counseling for PD. However, participants with PD and those with pathogenic variants had less favorable M-MICRA scores and lower satisfaction scores compared to those without disease or pathogenic variants. This information is valuable to providers performing genetic testing of and genetic counseling to people and families affected with PD. Individuals with PD and individuals with pathogenic variants may benefit from additional interventions.

Telehealth for genetic counseling: A systematic evidence review.

Telehealth options, such as telephone counseling or videoconferencing, for service delivery in genetic counseling are becoming more widely accepted. However, until now, there has not been a systematic review of the literature focused specifically on genetic counseling outcomes for telehealth. We performed a systematic evidence review to compare telehealth genetic counseling (THGC), including videoconferencing and telephone counseling, across specialties to in-person genetic counseling (IPGC) for a range of outcomes specific to patient and provider experiences and access to care. Several biomedical databases were queried up to January 11, 2021, to identify original research evaluating THGC. Through this search, 42 articles met the inclusion criteria including 13 randomized controlled trials and 29 non-randomized observational studies encompassing 13,901 patients. Most included studies focused only on cancer genetic counseling; however, adult, pediatric, and prenatal specialties were also represented. The majority of studies evaluated patient and/or access to care outcomes. Though most studies reported high patient satisfaction with THGC, as well as comparable rates of trust and rapport, confidence in privacy, health behavior changes, and psychosocial outcomes, few represented diverse populations. Data of provider experiences were limited and varied with more disadvantages noted compared with patient experiences, particularly in studies involving telephone genetic counseling. Studies consistently reported a decrease in the patients' costs and time required for travel when patients are seen via THGC compared to IPGC with a similar reduction in costs to the health system. Overall, results from our evidence synthesis suggest THGC is non-inferior or comparable to IPGC across many domains, even considering that many of the studies included in this review were conducted with telehealth systems, notably videoconferencing, that were less robust and reliable than what is available today. There are notable limitations within this body of literature, leading to potential uncertainty in the generalizability of our analysis. We outline several recommendations for future studies.

Clinical genetic counselor experience in the adoption of telehealth in the United States and Canada during the COVID-19 pandemic.

The COVID-19 pandemic has significantly impacted the service delivery model (SDM) of clinical genetic counseling across the United States and Canada. A cross-sectional survey was distributed to 4,956 genetic counselors (GCs) from the American Board of Genetic Counselors and Canadian Association of Genetic Counselors mailing lists in August 2020 to assess the change in utilization of telehealth for clinical genetic counseling during the COVID-19 pandemic compared with prior to the pandemic. Data from 411 eligible clinical genetic counselors on GC attitudes and their experiences prior to and during the pandemic were collected and analyzed to explore the change in SDM, change in appointment characteristics, change in billing practices, GC perceived benefits and limitations of telehealth, and prediction of future trends in SDM in the post-pandemic era. The study showed the overall utilization of audiovisual and telephone encounters increased by 43.4% and 26.2%, respectively. The majority of respondents who provided audiovisual and telephone encounters reported increased patient volume compared with prior to the pandemic, with an average increase of 79.4% and 42.8%, respectively. There was an increase of 69.4% of GCs rendering genetic services from home offices. The percentage of participants who billed for telehealth services increased from 45.7% before the pandemic to 80.3% during the pandemic. The top GC perceived benefits of telehealth included safety for high-risk COVID patients (95.2%) and saved commute time for patients (94.7%). The top GC perceived limitations of telehealth included difficulty to conduct physician evaluation/coordinating with healthcare providers (HCP) (73.7%) and difficulty addressing non-English speaking patients (68.5%). Overall, 89.6% of GCs were satisfied with telehealth; however, 55.3% reported uncertainty whether the newly adopted SDM would continue after the pandemic subsides. Results from this study demonstrate the rapid adoption of telehealth for clinical genetic counseling services as a result of the COVID-19 pandemic, an increase in billing for these services, and support the feasibility of telehealth for genetic counseling as a longer term solution to reach patients who are geographically distant.

The Promise and Pitfalls of Facebook Advertising: a Genetic Counselor's Perspective.

Facebook advertising is a powerful tool for increasing the outreach and recruitment of research participants. We describe our experience as genetic counselors within the context of an internet-based research study, recruiting subjects for a Parkinson disease (PD) biomarker study.

Connecting Gaucher and Parkinson Disease: Considerations for Clinical and Research Genetic Counseling Settings.

There are multiple autosomal recessive disorders in which carriers may be at risk for other diseases. This observation calls into question the previous understanding that carriers of autosomal recessive disorders escape clinical consequences. We also know that childhood genetic conditions may have adult disease counterparts (Zimran et al., The Israel Medical Association Journal: IMAJ, 16(11), 723-724, 2014). Individuals who have Gaucher disease and carriers of the disorder are at increased risk for a seemingly unrelated and complex neurological condition, Parkinson disease. Parkinson disease is, in part, caused by the same mutations in the GBA gene that lead to Gaucher disease, and the two conditions are thought to have shared pathophysiology. Briefly reviewed are how these two diseases historically became linked, where their paths cross, potential problems and considerations in disclosure of the link, and current guidelines and research in this area. Genetic counseling experience with a large Parkinson disease cohort is used as a starting point to question the state of clinical and nonclinical practice in disclosing this unusual connection We conclude that more research and discussion are needed to inform practice regarding the crossroads of Gaucher and Parkinson disease.

NIPT and Informed Consent: an Assessment of Patient Understanding of a Negative NIPT Result.

Since becoming clinically available in 2011, the use of noninvasive prenatal testing (NIPT) to screen for fetal aneuploidy has continued to increase. However, it has been questioned whether the education of patients undergoing NIPT consistently meets informed consent standards. We sought to evaluate patients' basic understanding of NIPT, such as conditions assessed and accuracy. In addition, we investigated patient self-assessment of NIPT knowledge and satisfaction with the testing process. We distributed an anonymous paper survey to pregnant women during prenatal visits following a negative NIPT result. The survey assessed patient NIPT knowledge, gathered pregnancy-specific and demographic information, and allowed respondents to rank their basic understanding of NIPT and provide written feedback about the testing process. A total of 95 completed and 3 partially completed surveys were returned. Participants scored lowest on knowledge questions involving whether a negative NIPT result ensures a healthy baby or eliminates the possibility of Down syndrome. Most perceived themselves to have a good basic understanding of NIPT and two-thirds of the written feedback proposed no changes to NIPT administration. Overall, most patients appear satisfied with their understanding of NIPT and the testing process, yet they may not fully appreciate the limitations of this screening method.

Delivering Genetic Test Results for Parkinson Disease: A Qualitative Approach to Provider Experiences in the PD GENEration Study.

Background and Objectives: The PD GENEration (PD GENE) study (NCT04057794) is an interventional clinical trial offering genetic testing with result disclosure and genetic counseling to individuals with Parkinson disease (PD). In general, experiences of those providing PD genetic testing and counseling in a research or clinical setting have not been extensively evaluated. In this study, providers' experiences when providing research result disclosure and genetic counseling to people with PD were explored with the goal of improving PD genetics services. Methods: Qualitative semistructured interviews of all neurologists and genetic counselors who performed genetic test result disclosure and genetic counseling to at least 5 participants in the pilot portion of the PD GENE study were conducted. An inductive thematic analysis of the transcribed interviews identified core themes and subthemes for "lessons learned" and "challenges encountered." Results: Interviews were conducted with 14 providers (7 neurologists and 7 genetic counselors) who described multiple lessons learned while disclosing genetic test results, including the ability to adapt to participant background and needs and the value of a well-structured and supportive study that also provides training and educational materials for the provider. Of importance, responses suggested that the PD GENE study answered a real need, highlighting a strong interest in the community. Providers also voiced several shared challenges including the complexities of PD and PD genetics, unexpected confusion on provider roles within a research study, and complicated family histories/dynamics. Discussion: Providers in the pilot portion of the PD GENE study encountered enthusiasm and strong engagement from many of the participants, and they, too, voiced significant satisfaction about their roles and the mission of the study. They learned valuable lessons, and their comfort providing genetic test result disclosure and genetic counseling grew as the study progressed. Although there were challenges, they were deemed manageable. The results from this qualitative study can inform both the expanded PD GENE study and other providers offering genetic testing and counseling to their patients in a neurology setting. It will also allow for targeted PD provider education.

Factors Influencing Patient Disclosure of Parkinson's Disease Genetic Testing Results to Relatives.

BACKGROUND: Persons with Parkinson's disease (PD) who have received genetic test results are faced with the decision of whether, and how, to share that information with family. Studies in other specialties have shown high rates of disclosure motivated by a sense of responsibility. Rates of, and attitudes surrounding, disclosure have yet to be reported in this population. OBJECTIVES: To explore the disclosure practices and motivations of patients with PD regarding genetic test results, allowing insight to guide genetic counseling and navigation of test result discussions. METHODS: A cross-sectional online survey was distributed to adults with PD and previous genetic test results. Survey questions assessed demographics, genetic testing results and delivery, sharing behaviors, perceptions of PD, and motivations and barriers to family disclosure. RESULTS: Among respondents, 88.9% shared results with at least one family member, most often a child (73.5%) or sibling (65.4%). Seventy-four percent reported sharing results with someone outside of their family, most frequently a friend (88.4%). The most common motivation for disclosure was the perception that family members would want to know. Barriers to disclosure were lack of close relationships, understanding results, and perceived utility. CONCLUSIONS: Disclosure rates in this PD population were consistent with those in previously reported populations. Motivations were anchored in perceptions of utility and family desire for information, suggesting a need to adjust patient education to improve retention and to explore family dynamics and perceptions of results.

Participant-reported personal utility of genetic testing for Parkinson's disease and interest in clinical trial participation.

Genetic testing for Parkinson's disease (PD) is infrequently performed due to perceptions of low utility. We investigated the personal utility in PD GENEration and how results lead to enrollment in additional research studies. Participants (n = 972) underwent genetic testing, results disclosure, genetic counseling, and completed a survey examining the perceived personal utility of their results and interest in participating in additional studies. Most participants found their genetic test results useful, including satisfying curiosity (81%), feeling good about helping the medical community (80%), and having information to share with family (77%). There were no significant differences in responses based on result type. Forty-five percent of participants expressed interest in participating in research studies; whereas 16% of participants confirmed enrollment. Our results suggest that participants find personal utility in genetic testing regardless of results. Although participants may be interested in enrolling in additional research, they may need support and resources.

Readiness for Parkinson's disease genetic testing and counseling in patients and their relatives in urban settings in the Dominican Republic.

Genetic testing for Parkinson's disease (PD) is increasing globally, and genetic counseling is an important service that provides information and promotes understanding about PD genetics and genetic testing. PD research studies have initiated outreach to underrepresented regions in North America, including regions in Latin America, such as the Dominican Republic (DR); some studies may include return of genetic test results. Thus, understanding what individuals know about PD, genetic testing for PD, and their interest in speaking with a genetic counselor, is crucial when assessing readiness. In this cross-sectional study, a survey was distributed to people with Parkinson's disease (PwP) and their unaffected biological relatives in the DR. Questions assessed genetics knowledge, attitude toward genetic testing, and interest in genetic testing and counseling. Of 45 participants, 69% scored the maximum on the attitude scale, indicating an overall positive attitude toward genetic testing; 95% indicated interest in genetic testing for PD, and 98% were at least somewhat interested in meeting with a genetic counselor. The mean PD genetics knowledge score was similar to previously published data. Through free text responses, participants expressed a desire to know more about PD treatment and management, prevention, cause, and their personal risk for PD. These results provide further evidence of readiness for genetic testing in this country but also underscore some gaps in knowledge that should be addressed with targeted educational efforts, as part of building genetic testing and counseling capacities.

The commercial genetic testing landscape for Parkinson's disease.

INTRODUCTION: There have been no specific guidelines regarding which genes should be tested in the clinical setting for Parkinson's disease (PD) or parkinsonism. We evaluated the types of clinical genetic testing offered for PD as the first step of our gene curation. METHODS: The National Institutes of Health (NIH) Genetic Testing Registry (GTR) was queried on 12/7/2020 to identify current commercial PD genetic test offerings by clinical laboratories, internationally. RESULTS: We identified 502 unique clinical genetic tests for PD, from 28 Clinical Laboratory Improvement Amendments (CLIA)-approved clinical laboratories. These included 11 diagnostic PD panels. The panels were notable for their differences in size, ranging from 5 to 62 genes. Five genes for variant query were included in all panels (SNCA, PRKN, PINK-1, PARK7 (DJ1), and LRRK2). Notably, the addition of the VPS35 and GBA genes was variable. Panel size differences stemmed from inclusion of genes linked to atypical parkinsonism and dystonia disorders, and genes in which the link to PD causation is controversial. CONCLUSION: There is an urgent need for expert opinion regarding which genes should be included in a commercial laboratory multi-gene panel for PD.

Genetic Testing for Parkinson Disease: Are We Ready?

PURPOSE OF REVIEW: With the advent of precision medicine and demand for genomic testing information, we may question whether it is time to offer genetic testing to our patients with Parkinson disease (PD). This review updates the current genetic landscape of PD, describes what genetic testing may offer, provides strategies for evaluating whom to test, and provides resources for the busy clinician. RECENT FINDINGS: Patients with PD and their relatives, in various settings, have expressed an interest in learning their PD genetic status; however, physicians may be hesitant to widely offer testing due to the perceived low clinical utility of PD genetic test results. The rise of clinical trials available for patients with gene-specific PD and emerging information on genotype-phenotype correlations are starting to shift this discussion about testing. SUMMARY: By learning more about the various genetic testing options for PD and utility of results for patients and their care, clinicians may become more comfortable with widespread PD genetic testing in the research and clinical setting.