Genetic testing and Parkinson disease: assessment of patient knowledge, attitudes, and interest

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.

Louis EK, Noyce AJ. Ethical Considerations for Identifying Individuals in the Prodromal/Early Phase of Parkinson's Disease: A Narrative Review

The ability to identify individuals in the prodromal phase of Parkinson's disease has improved in recent years, raising the question of whether and how those affected should be informed about the risk of future disease. Several studies investigated prognostic counselling for individuals with isolated REM sleep behavior disorder and have shown that most patients want to receive information about prognosis, but autonomy and individual preferences must be respected. However, there are still many unanswered questions about risk disclosure or early diagnosis of PD, including the impact on personal circumstances, cultural preferences and specific challenges associated with different profiles of prodromal symptoms, genetic testing or biomarker assessments. This narrative review aims to summarize the current literature on prognostic counselling and risk disclosure in PD, as well as highlight future perspectives that may emerge with the development of new biomarkers and their anticipated impact on the definition of PD.

Genetic literacy and attitude towards genetic testing in patients with Parkinson's disease and their caregivers: A review of literature

BACKGROUND

Genetic literacy refers to an individual's ability to understand the basics of genetic concepts and apply them to health-related decisions. The level of genetic literacy influences attitude towards genetic testing and is, in turn, influenced by several other factors. Clinicians must be aware of the genetic literacy of their patients and their caregivers before advising genetic testing and/or undertaking pre and post-test counseling.

METHOD

A systematic review of literature in PubMed was carried out using keywords "Genetic testing", "Genetic counseling", "Knowledge", "Attitude", "Parkinson's disease" in various combinations.

RESULTS

Seven eligible studies with a total of 1837 individuals (patients with PD-1355 and patient caregivers-482) were identified. More than half the participants were well-versed in basic concepts of genetics (57.8%) and risks of inheriting PD (60.5%) while less than 10% were aware regarding the contribution of specific genes (e.g. LRRK2). Interest in diagnosis, treatment, prevention and facilitating PD research were central themes for positive attitude while apprehensions revolving around impact on employment and insurance and non-benefit were associated with negative attitudes. Possible associations included greater knowledge scores with positive attitudes towards genetic testing and older age for negative attitude towards testing. Insufficient data on attitudes toward prenatal testing, presymptomatic testing and clinicians' attitude toward testing was identified.

CONCLUSION

Patients with PD and their caregivers are aware of the role of genetics in the etiopathogenesis of their disease, which contributes to their positive attitude towards testing. Further studies exploring negative attitudes towards testing will help overcome the hurdles in genetic testing and counseling in this cohort of patients.

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.

User and Usability Testing of a Web-Based Genetics Education Tool for Parkinson Disease: Mixed Methods Study

BACKGROUND

Genetic testing is essential to identify research participants for clinical trials enrolling people with Parkinson disease (PD) carrying a variant in the glucocerebrosidase (GBA) or leucine-rich repeat kinase 2 (LRRK2) genes. The limited availability of professionals trained in neurogenetics or genetic counseling is a major barrier to increased testing. Telehealth solutions to increase access to genetics education can help address issues around counselor availability and offer options to patients and family members.

OBJECTIVE

As an alternative to pretest genetic counseling, we developed a web-based genetics education tool focused on GBA and LRRK2 testing for PD called the Interactive Multimedia Approach to Genetic Counseling to Inform and Educate in Parkinson's Disease (IMAGINE-PD) and conducted user testing and usability testing. The objective was to conduct user and usability testing to obtain stakeholder feedback to improve IMAGINE-PD.

METHODS

Genetic counselors and PD and neurogenetics subject matter experts developed content for IMAGINE-PD specifically focused on GBA and LRRK2 genetic testing. Structured interviews were conducted with 11 movement disorder specialists and 13 patients with PD to evaluate the content of IMAGINE-PD in user testing and with 12 patients with PD to evaluate the usability of a high-fidelity prototype according to the US Department of Health and Human Services Research-Based Web Design & Usability Guidelines. Qualitative data analysis informed changes to create a final version of IMAGINE-PD.

RESULTS

Qualitative data were reviewed by 3 evaluators. Themes were identified from feedback data of movement disorder specialists and patients with PD in user testing in 3 areas: content such as the topics covered, function such as website navigation, and appearance such as pictures and colors. Similarly, qualitative analysis of usability testing feedback identified additional themes in these 3 areas. Key points of feedback were determined by consensus among reviewers considering the importance of the comment and the frequency of similar comments. Refinements were made to IMAGINE-PD based on consensus recommendations by evaluators within each theme at both user testing and usability testing phases to create a final version of IMAGINE-PD.

CONCLUSIONS

User testing for content review and usability testing have informed refinements to IMAGINE-PD to develop this focused, genetics education tool for GBA and LRRK2 testing. Comparison of this stakeholder-informed intervention to standard telegenetic counseling approaches is ongoing.

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.

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.

The Genetic Testing Experience of Individuals with Parkinson's Disease

Background

The perspective and experiences of individuals with Parkinson's disease (PD) regarding genetic testing is limited.

Objectives

To determine if anticipated benefits and negative consequences of genetic testing noted in prior studies have occurred in a surveyed group of patients with PD and to identify reasons why some individuals with PD have not had testing.

Methods

Individuals were surveyed from 22 support/advocacy groups throughout the US. Information about patient demographics and genetic testing were assessed, along with the consequences experienced after testing or anticipated by those who have not had testing. Descriptive statistics, Pearson correlation coefficient, ANOVA, and independent sample t-test were utilized for data analysis.

Results

Of the genetic testing group (n = 78), most received testing through a research study (44.9%) or a Direct-to-Consumer company (46.2%). Most did not meet with a genetic counselor before (87.2%) or after testing (64.1%). Fewer positive and fewer negative consequences were reported after testing compared to the consequences anticipated by those who have not undergone testing (P < 0.001, all comparisons). Of the non-genetic testing group (n = 166), 49.4% did not undergo testing because they were not aware it was available and 38.0% because their doctor did not offer it.

Conclusions

Findings demonstrate the need for providers to have genetic testing discussions with PD patients, who may otherwise seek testing via Direct-to-Consumer companies or be unaware it is available. Collaborations with genetic counselors trained in providing anticipatory guidance may assist patients in forming more realistic expectations regarding the consequences experienced after genetic testing for PD.

Predicting attitudes towards screening for neurodegenerative diseases using OCT and artificial intelligence: Findings from a literature review

Recent developments in artificial intelligence (AI) and machine learning raise the possibility of screening and early diagnosis for neurodegenerative diseases, using 3D scans of the retina. The eventual value of such screening will depend not only on scientific metrics such as specificity and sensitivity but, critically, also on public attitudes and uptake. Differential screening rates for various screening programmes in England indicate that multiple factors influence uptake. In this narrative literature review, some of these potential factors are explored in relation to predicting uptake of an early screening tool for neurodegenerative diseases using AI. These include: awareness of the disease, perceived risk, social influence, the use of AI, previous screening experience, socioeconomic status, health literacy, uncontrollable mortality risk, and demographic factors. The review finds the strongest and most consistent predictors to be ethnicity, social influence, the use of AI, and previous screening experience. Furthermore, it is likely that factors also interact to predict the uptake of such a tool. However, further experimental work is needed both to validate these predictions and explore interactions between the significant predictors.

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.

Young Onset Parkinson's Disease: A Modern and Tailored Approach

In people with young onset Parkinson’s disease (YOPD), onset of symptoms is between 21 and 40 years of age. The distinction between YOPD and late-onset Parkinson’s disease is supported by genetic differences (a genetic etiology is more common in people with YOPD) and clinical differences (e.g., dystonia and levodopa-induced dyskinesias are more common inYOPD). Moreover, people with YOPD tend to have different family and societal engagements compared to those with late-onset PD. These unique features have implications for clinical management, and call for a tailored multidisplinary approach involving shared-decision making.

Integrated sequencing and array comparative genomic hybridization in familial Parkinson disease

Objective

To determine how single nucleotide variants (SNVs) and copy number variants (CNVs) contribute to molecular diagnosis in familial Parkinson disease (PD), we integrated exome sequencing (ES) and genome-wide array-based comparative genomic hybridization (aCGH) and further probed CNV structure to reveal mutational mechanisms.

Methods

We performed ES on 110 subjects with PD and a positive family history; 99 subjects were also evaluated using genome-wide aCGH. We interrogated ES and aCGH data for pathogenic SNVs and CNVs at Mendelian PD gene loci. We confirmed SNVs via Sanger sequencing and further characterized CNVs with custom-designed high-density aCGH, droplet digital PCR, and breakpoint sequencing.

Results

Using ES, we discovered individuals with known pathogenic SNVs in GBA (p.Glu365Lys, p.Thr408Met, p.Asn409Ser, and p.Leu483Pro) and LRRK2 (p.Arg1441Gly and p.Gly2019Ser). Two subjects were each double heterozygotes for variants in GBA and LRRK2. Based on aCGH, we additionally discovered cases with an SNCA duplication and heterozygous intragenic GBA deletion. Five additional subjects harbored both SNVs (p.Asn52Metfs*29, p.Thr240Met, p.Pro437Leu, and p.Trp453*) and likely disrupting CNVs at the PRKN locus, consistent with compound heterozygosity. In nearly all cases, breakpoint sequencing revealed microhomology, a mutational signature consistent with CNV formation due to DNA replication errors.

Conclusions

Integrated ES and aCGH yielded a genetic diagnosis in 19.3% of our familial PD cohort. Our analyses highlight potential mechanisms for SNCA and PRKN CNV formation, uncover multilocus pathogenic variation, and identify novel SNVs and CNVs for further investigation as potential PD risk alleles.

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.

Ethical issues in susceptibility genetic testing for late-onset neurodegenerative diseases

Genome-wide association studies have revolutionized our understanding of the genetic architecture of complex traits and diseases over the last decade. This knowledge is enabling clinicians, researchers, and direct-to-consumer genetics companies to conduct disease susceptibility testing based on powerful methods such as polygenic risk scoring. However, these technologies raise a set of complex ethical, legal, social, and policy considerations. Here we review and discuss a series of ethical dilemmas associated with susceptibility genetic testing for the two most common late-onset neurodegenerative diseases, Alzheimer's and Parkinson's disease, including testing in asymptomatic individuals. Among others, these include informed consent, disclosure of results and unexpected findings, mandatory screening, privacy and confidentiality, and stigma and genetic discrimination. Importantly, appropriate counseling is a deciding factor for the ethical soundness of genetic testing, which poses a challenge for the regulation of these tests and the training of healthcare professionals. As genetic knowledge about these diseases continues growing and genetic testing becomes more widespread, it is increasingly important to raise awareness among researchers, medical practitioners, genetic counselors, and decision makers about the ethical, legal, and social issues associated with genetic testing for polygenic diseases.

Patient Knowledge and Attitudes towards Genetic Testing in Parkinson's Disease Subjects with Deep Brain Stimulation

Objectives

As genetic testing is becoming more widely commercially available for Parkinson's disease (PD) and may have implications regarding clinical outcomes for deep brain stimulation (DBS) and other therapies, we aimed to determine patient knowledge and attitudes towards genetic testing.

Methods

A sample of 88 PD subjects with bilateral STN-DBS completed a Genetic Attitudes Questionnaire (GAQ). Knowledge and attitudes towards genetic testing were assessed.

Results

The mean percent of correct responses regarding genetic testing knowledge was 58.5%. Nearly 90% of subjects were unfamiliar with Genetic Information Nondiscrimination Act (GINA). The most important reasons subjects cited in deciding whether to undergo genetic testing included (1) to be a candidate for clinical trials if positive, (2) to learn that they do not carry a mutation, and (3) because a healthcare provider had recommended it. Individuals who influence decision-making include spouses and children. About 88% of subjects would share results with spouses, children, and siblings.

Discussion

These results reveal that there is a major knowledge gap regarding genetic testing in PD and the implications of testing results on treatment, work, insurance, and privacy. Also, subjects would mainly seek genetic testing to participate in clinical trials, with spouses and children being the key stakeholders in decision-making.

Physician and patient determinants of prognostic counseling in idiopathic REM sleep-behavior disorder

OBJECTIVES/BACKGROUND

Prognostic counseling about the risk for developing overt neurodegenerative disorders for patients with idiopathic REM sleep-behavior disorder (iRBD) and isolated REM sleep without atonia (iRSWA) is difficult, given lack of disease-modifying interventions and uncertainty in accurate prognostication for individuals. We aimed to analyze patient and physician characteristics associated with documented prognostic discussions for patients with iRBD and iRSWA.

PATIENTS/METHODS

We retrospectively reviewed the medical records for 138 (112 iRBD and 26 iRSWA) patients seen at the Mayo Clinic between 2012 and 2015. We analyzed physician and patient demographics, initial complaint, and other information discussed during office visits. We then comparatively analyzed the impact of physician and patient characteristics on documented prognostic discussions using Chi Square or Fischer's exact test.

RESULTS

Mean iRBD patient age was 65.0 ± 13.0, and mean iRSWA age was 58 ± 15 years. Seventy-eight (69.6%) iRBD and 22 (84.6%) iRSWA patients were men. Sixty-two (55%) iRBD and three (12%) iRSWA patients received prognostic counseling about phenoconversion risk. iRBD was a secondary complaint in 67 (59.8%). Patients over age 60 years and those having iRBD as a chief complaint more frequently received prognostic discussions than those with opposite characteristics (all p < 0.05). Patient sex and antidepressant use were not associated with counseling. Sleep neurologists disclosed prognostic information most frequently, with male more likely than female clinicians to disclose prognoses.

CONCLUSIONS

Several patient and physician characteristics appear to influence documented prognostic counseling for iRBD/RSWA patients. Future studies of iRBD/RSWA patients' preferences are needed to clarify ethically appropriate physician-patient communication concerning prognosis.

GBA-Associated Parkinson's Disease and Other Synucleinopathies

PURPOSE OF REVIEW

GBA mutations are the most common known genetic cause of Parkinson's disease (PD). Its biological pathway may be important in idiopathic PD, since activity of the enzyme encoded by GBA, glucocerebrosidase, is reduced even among PD patients without GBA mutations. This article describes the structure and function of GBA, reviews recent literature on the clinical phenotype of GBA PD, and suggests future directions for research, counseling, and treatment.

RECENT FINDINGS

Several longitudinal studies have shown that GBA PD has faster motor and cognitive progression than idiopathic PD and that this effect is dose dependent. New evidence suggests that GBA mutations may be important in multiple system atrophy. Further, new interventional studies focusing on GBA PD are described. These studies may increase the interest of PD patients and caregivers in genetic counseling. GBA mutation status may help clinicians estimate PD progression, though mechanisms underlying GBA and synucleinopathy require further understanding.

High Performance Liquid Chromatography-Mass Spectrometry (LC-MS) Based Quantitative Lipidomics Study of Ganglioside-NANA-3 Plasma to Establish Its Association with Parkinson's Disease Patients

Background

It is well known that, pathologically, Parkinson’s disease is a common neurodegenerative disorder. In Parkinson’s disease, the protein which is abundant in the human brain, alpha-synuclein, accumulates inside the nerve cells. In this situation, dysregulation of lipid metabolism performs a crucial role; however, its association with Parkinson’s disease is has not yet been explored.

Material/Methods

We performed a high-performance liquid chromatography-mass spectrometry-derived quantitative lipidomics study to analyze the profile of lipidomic plasma obtained from 170 PD patients and 120 controls, taken from our hospital. A logistic regression model was used for analysis in each of the lipid species having all major classes of glycerolipids, sterols, sphingolipids, and glycerophospholipids.

Results

We observed that there are differences in the plasma concentrations of 2 lipid subclasses, triacylglycerides and ganglioside-NANA-3, between control and Parkinson’s disease participants. The most significant difference between both the participants was observed in the case of ganglioside-NANA-3 plasma concentration (1.293±0.029 pmol/μl versus 1.488±0.041 pmol/μl, respectively) after normalizing it with respect to total lipid. Further, a group of 22 glucosylceramide and ganglioside-NANA-3 species concentration was used for receiver operating characteristic curve analysis after normalizing it with respect to total lipid. The results were quite consistent with previously reported biomarker results.

Conclusions

Our results show that there is quite good association between high concentration of ganglioside-NANA-3 species and Parkinson’s disease. Interestingly, the same metabolic pathway of glucosylceramide, which is a substrate of the enzyme glucocerebrosidase, has been linked with Parkinson’s disease, which is at last followed by ganglioside-NANA-3. These results are supported by earlier works in which lower glucocerebrosidase activity has led to risk of the disease.

Patients with Amyotrophic Lateral Sclerosis Have High Interest in and Limited Access to Genetic Testing

Although genetic testing for amyotrophic lateral sclerosis (ALS) is widely available, it is unknown what proportion of patients with ALS have access to genetic counseling and testing, and patient attitudes towards ALS genetic testing have not been studied. We conducted a national survey of ALS patients enrolled in the Agency for Toxic Substances and Disease Registry, which consisted of multiple choice questions and two 12 item Likert scale series assessing respondents' experience with and attitude toward genetic testing. The survey had an 8 % response rate, with 449 completed responses. Genetic testing was offered to 33.4 % and completed by 67.1 % of those offered. A minority of respondents (12.5 %) saw a genetic counselor, and were much more likely to be offered genetic testing (p = 0.0001). Respondents with a family history of ALS (8.4 %) were more likely to be offered testing (p = 0.0001) and complete testing (p = 0.05). Respondents with a family history of ALS were more likely to report a favorable attitude towards genetic testing (p = 0.0003), as were respondents who saw a genetic counselor (p = 0.02). The majority of respondents (82.7 %) felt that genetic testing should be offered to all patients with ALS. Our results indicate that ALS patients may have limited access to genetic testing, but perceive benefit from this service. Development of practice guidelines for genetic testing in ALS, to include the routine offer of genetic counseling, may result in broader and more consistent access to these services.

Knowledge of Genetics and Attitudes toward Genetic Testing among College Students in Saudi Arabia

BACKGROUND

Genetic testing has been gradually permeating the practice of medicine. Health-care providers may be confronted with new genetic approaches that require genetically informed decisions which will be influenced by patients' knowledge of genetics and their attitudes toward genetic testing. This study assesses the knowledge of genetics and attitudes toward genetic testing among college students.

METHODS

A cross-sectional study was conducted using a multistage stratified sample of 920 senior college students enrolled at King Abdulaziz University, Saudi Arabia. Information regarding knowledge of genetics, attitudes toward genetic testing, and sociodemographic data were collected using a self-administered questionnaire.

RESULTS

In general, students had a good knowledge of genetics but lacked some fundamentals of genetics. The majority of students showed positive attitudes toward genetic testing, but some students showed negative attitudes toward certain aspects of genetic testing such as resorting to abortion in the case of an untreatable major genetic defect in an unborn fetus. The main significant predictors of knowledge were faculty, gender, academic year, and some prior awareness of 'genetic testing'. The main significant predictors of attitudes were gender, academic year, grade point average, and some prior awareness of 'genetic testing'.

CONCLUSION

The knowledge of genetics among college students was higher than has been reported in other studies, and the attitudes toward genetic testing were fairly positive. Genetics educational programs that target youths may improve knowledge of genetics and create a public perception that further supports genetic testing.

Usefulness of Genetic Testing in PD and PD Trials: A Balanced Review

An increasing proportion of the individual and population risk to develop Parkinson’s disease (PD) can be explained by genetic variants of different effect strength, forming a continuum from rare high penetrance gain or loss of function mutations to relatively common genetic risk variants that only mildly modify disease risk. In the coming years, further advances in molecular genetic technologies, in particular the increasing use of next generation sequencing, is likely to generate a wealth of new knowledge about the genetic basis of PD. Although specific treatments for PD based on the underlying genetic etiology will probably not be available in the near future, genetic testing is therefore likely to play an increasing role, both in the counselling of individual patients and their families with respect to the expected disease course and recurrence risks, and in the stratification of patient groups in clinical trials. Thus, the usefulness of genetic testing strongly depends on question asked and needs to be considered within each particular setting.

Information Avoidance Tendencies, Threat Management Resources, and Interest in Genetic Sequencing Feedback

BACKGROUND

Information avoidance is a defensive strategy that undermines receipt of potentially beneficial but threatening health information and may especially occur when threat management resources are unavailable.

PURPOSE

We examined whether individual differences in information avoidance predicted intentions to receive genetic sequencing results for preventable and unpreventable (i.e., more threatening) disease and, secondarily, whether threat management resources of self-affirmation or optimism mitigated any effects.

METHODS

Participants (N = 493) in an NIH study (ClinSeq®) piloting the use of genome sequencing reported intentions to receive (optional) sequencing results and completed individual difference measures of information avoidance, self-affirmation, and optimism.

RESULTS

Information avoidance tendencies corresponded with lower intentions to learn results, particularly for unpreventable diseases. The association was weaker among individuals higher in self-affirmation or optimism, but only for results regarding preventable diseases.

CONCLUSIONS

Information avoidance tendencies may influence decisions to receive threatening health information; threat management resources hold promise for mitigating this association.

Guiding Oncology Patients Through the Maze of Precision Medicine

As the role of genomics in health care grows, patients increasingly require adequate genetic literacy to fully engage in their care. This study investigated a model for delivering consumer-friendly genetic information to improve understanding of precision medicine using health literacy and learning style principles. My Cancer Genome (MCG), a freely available cancer decision support tool, was used as a testbed. MCG content on a melanoma tumor mutation, BRAF V600E, was translated to a 6th-grade reading level, incorporating multiple learning modalities. A total of 90 patients and caregivers were recruited from a melanoma clinic at an academic medical center and randomized to 3 groups. Group A (control) received an exact copy of text from MCG. Group B was given the same content with hyperlinks to videos explaining key genetic concepts, identified and labeled by the team as knowledge pearls. Group C received the translated content with the knowledge pearls embedded. Changes in knowledge were measured through pre and post questionnaires. Group C showed the greatest improvement in knowledge. The study results demonstrate that providing information based on health literacy and learning style principles can improve patients' understanding of genetic concepts, thus increasing their likelihood of taking an active role in any decision making concerning their health.

Associations and implications of low health literacy in Parkinson's Disease

BACKGROUND

Low health literacy (HL) indicates a limited ability to understand and use basic information to make appropriate healthcare decisions. While low HL is associated with higher morbidity, mortality, and healthcare costs in multiple chronic conditions, little is known about HL and its associations in Parkinson's disease (PD).

METHODS

Cross-sectional study of non-demented adults with PD participating in the National Parkinson Foundation Parkinson's Outcomes Project at the University of Pennsylvania. Subjects were administered two brief HL assessments-the Rapid Estimate of Adult Literacy in Medicine-Short Form (REALM-SF), a word-recognition test, and the Newest Vital Sign (NVS), a test of literacy, numeracy and understanding of health information-as well as demographic and clinical questionnaires. Adverse outcomes included falls in the 3 months preceding the study visit, and hospital admissions, emergency room visits, infections, or injuries in the preceding year. Caregiver burden was measured using the Multidimensional Caregiver Strain Index.

RESULTS

168 subjects completed both HL screens (mean 65.8 years, 65.5% male, 65.2% Hoehn & Yahr Stage 2). Using the REALM-SF, 97.6% of subjects had adequate HL. Using the NVS, however, 29.8% had low HL, which was associated with older age, lower education, male gender, greater disease severity, and poorer cognition. Low HL was associated with hospital admission and increased caregiver burden.

CONCLUSIONS

Low HL is common and associated with greater caregiver burden and a higher likelihood of hospitalization in patients with PD. Since HL is associated with both disease severity and adverse outcomes, it may be an important, modifiable contributor to morbidity.

Measuring genetic knowledge: a brief survey instrument for adolescents and adults

Basic knowledge of genetics is essential for understanding genetic testing and counseling. The lack of a written, English language, validated, published measure has limited our ability to evaluate genetic knowledge of patients and families. Here, we begin the psychometric analysis of a true/false genetic knowledge measure. The 18-item measure was completed by parents of children with congenital heart defects (CHD) (n = 465) and adolescents and young adults with CHD (age: 15-25, n = 196) with a mean total correct score of 12.6 [standard deviation (SD) = 3.5, range: 0-18]. Utilizing exploratory factor analysis, we determined that one to three correlated factors, or abilities, were captured by our measure. Through confirmatory factor analysis, we determined that the two factor model was the best fit. Although it was necessary to remove two items, the remaining items exhibited adequate psychometric properties in a multidimensional item response theory analysis. Scores for each factor were computed, and a sum-score conversion table was derived. We conclude that this genetic knowledge measure discriminates best at low knowledge levels and is therefore well suited to determine a minimum adequate amount of genetic knowledge. However, further reliability testing and validation in diverse research and clinical settings is needed.

Interest in genetic testing in Ashkenazi Jewish Parkinson's disease patients and their unaffected relatives

Our objective was to explore interest in genetic testing among Ashkenazi Jewish (AJ) Parkinson's Disease (PD) cases and first-degree relatives, as genetic testing for LRRK2 G2019S is widely available. Approximately 18 % of AJ PD cases carry G2019S mutations; penetrance estimations vary between 24 and 100 % by age 80. A Genetic Attitude Questionnaire (GAQ) was administered at two New York sites to PD families unaware of LRRK2 G2019S mutation status. The association of G2019S, age, education, gender and family history of PD with desire for genetic testing (outcome) was modeled using logistic regression. One-hundred eleven PD cases and 77 relatives completed the GAQ. Both PD cases and relatives had excellent PD-specific genetic knowledge. Among PD, 32.6 % "definitely" and 41.1 % "probably" wanted testing, if offered "now." Among relatives, 23.6 % "definitely" and 36.1 % "probably" wanted testing "now." Desire for testing in relatives increased incrementally based on hypothetical risk of PD. The most important reasons for testing in probands and relatives were: if it influenced medication response, identifying no mutation, and early prevention and treatment. In logistic regression, older age was associated with less desire for testing in probands OR = 0.921 95%CI 0.868-0.977, p = 0.009. Both probands and relatives express interest in genetic testing, despite no link to current treatment or prevention.

Promoting healthy dietary behaviour through personalised nutrition: technology push or technology pull?

The notion of educating the public through generic healthy eating messages has pervaded dietary health promotion efforts over the years and continues to do so through various media, despite little evidence for any enduring impact upon eating behaviour. There is growing evidence, however, that tailored interventions such as those that could be delivered online can be effective in bringing about healthy dietary behaviour change. The present paper brings together evidence from qualitative and quantitative studies that have considered the public perspective of genomics, nutrigenomics and personalised nutrition, including those conducted as part of the EU-funded Food4Me project. Such studies have consistently indicated that although the public hold positive views about nutrigenomics and personalised nutrition, they have reservations about the service providers' ability to ensure the secure handling of health data. Technological innovation has driven the concept of personalised nutrition forward and now a further technological leap is required to ensure the privacy of online service delivery systems and to protect data gathered in the process of designing personalised nutrition therapies.

Genetic testing of LRRK2 in Parkinson's disease: is there a clinical role?

Genetic testing has played an important role for the diagnosis of many rare monogenic disorders. However, the role and limitations of genetic testing have generated considerable debate in the medical community. In recent years, the identification of several monogenic genes in Parkinson's disease (PD), a common neurodegenerative disorder, has led to calls for genetic testing guidelines for this disorder. Genetic testing of LRRK2 provides an excellent platform to highlight some of the pertinent issues (generic and specific) related to genetic testing in PD. The identification of a common recurrent mutation (G2019S) worldwide provides an opportunity for developing guidelines that are applicable internationally. However, the incomplete penetrance of the mutation and the lack of clarity of the pathogenicity of many other reported LRRK2 mutations call for cautious implementation of genetic testing programs. The clinical utility of genetic testing is compounded by easy accessibility of Direct to Consumer genetic services and the relative lack of regulation on reliability of service providers in internet advertisements. Based on current literature, genetic testing of LRRK2 (particularly for G2019S) certainly has a clinical role, though it is applicable primarily in select scenarios and in certain at-risk populations.

Cardiac genetic testing: a single-center pilot study of a Dominican population

The impact of undergoing genetic testing in a Dominican population is not well understood. The objective of this investigation was to evaluate the psychological well-being and perceived cardiac risk among Dominicans who underwent genetic testing. Participants completed a qualitative interview and the Short Form-36 (SF-36) questionnaire after cardiac genetic testing. There were 31 subjects evaluated (mean age 42 ± 11 years). Participants revealed three common themes: (a) fear of dying prematurely, (b) guilt of possibly passing on a mutation to their children, and (c) fear of having an implantable cardioverter defibrillator (ICD) shock. Physical components of the SF-36 were within normal limits (46.2 ± 6.6) but elevated for mental components (59.9 ± 5.3). The quality of life and specific themes results determined in this investigation warrant further research in the Dominican population.

Cognitive and motor function in long-duration PARKIN-associated Parkinson disease

IMPORTANCE

Data on the long-term cognitive outcomes of patients with PARKIN-associated Parkinson disease (PD) are unknown but may be useful when counseling these patients.

OBJECTIVE

Among patients with early-onset PD of long duration, we assessed cognitive and motor performances, comparing homozygotes and compound heterozygotes who carry 2 PARKIN mutations with noncarriers.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study of 44 participants at 17 different movement disorder centers who were in the Consortium on Risk for Early-Onset PD study with a duration of PD greater than the median duration (>14 years): 4 homozygotes and 17 compound heterozygotes (hereafter referred to as carriers) and 23 noncarriers.

MAIN OUTCOMES AND MEASURES

Unified Parkinson Disease Rating Scale Part III (UPDRS-III) and Clinical Dementia Rating scores and neuropsychological performance. Linear regression models were applied to assess the association between PARKIN mutation status and cognitive domain scores and UPDRS-III scores. Models were adjusted for age, education, disease duration, language, and levodopa equivalent daily dose.

RESULTS

Carriers had an earlier age at onset of PD (P < .001) and were younger (P = .004) at time of examination than noncarriers. They performed better than noncarriers on the Mini-Mental State Examination (P = .010) and were more likely to receive lower scores on the Clinical Dementia Rating (P = .003). In multivariate analyses, carriers performed better than noncarriers on the UPDRS-III (P = .02) and on tests of attention (P = .03), memory (P = .03), and visuospatial (P = .02) cognitive domains.

CONCLUSIONS AND RELEVANCE

In cross-sectional analyses, carriers demonstrated better cognitive and motor performance than did noncarriers with long disease duration, suggesting slower disease progression. A longitudinal follow-up study is required to confirm these findings.

Knowledge and attitudes towards genetic testing in those affected with Parkinson's disease

Advances in genetic tests provide valuable information for clinicians and patients around risks and inheritance of Parkinson's Disease (PD); however, questions arise whether those affected or at risk of PD will want genetic testing, particularly given that there are no preventive or disease-modifying therapies currently available. This study sought to determine knowledge and attitudes toward genetic testing for those affected with PD. A cross-sectional study was undertaken using a standardized questionnaire with six multi-choice genetic knowledge and 17 multi-choice attitude items. Participants were selected from a registry of people affected with PD living in Queensland, Australia. Half of the selected index cases had a family history of PD. Ordinal regression was used to evaluate the association between support for genetic testing and demographic, knowledge, and other attitudinal factors. The level of genetic knowledge was relatively low (37 % correct responses). The vast majority supported diagnostic testing (97 %) and 90 % would undertake a genetic test themselves. Support for predictive was lower (78 %) and prenatal genetic testing had the least support (58 %). Benefits of testing were identified as the ability to know the child's risk, seek therapies, and helping science with finding a cure. Concerns about genetic testing included potential emotional reactions and test accuracy. Genetic knowledge was not significantly associated with attitudes towards genetic testing. Patients with PD have strong interest in genetic testing for themselves with support for diagnostic testing but less support for predictive and prenatal testing. Genetic knowledge was unrelated to testing attitudes.

Knowledge of and interest in genetic results among Parkinson disease patients and caregivers

The purpose of the study is to investigate Parkinson disease (PD) patients' and caregivers' knowledge of and interest in genetic testing. Gaucher disease (GD) results from recessive mutations in glucocerebrosidase (GBA). Both heterozygote GBA carriers and GD patients are at greater risk for PD. Studies regarding knowledge of and interest in genetic testing have been limited and have not offered genetic results to participants. In this study, 353 PD patients and 180 caregivers were recruited to a PD genetic study. The association between GD, GBA mutations and PD was described to participants who reported their familiarity with genetic terms, answered questions on genetic concepts, and indicated their interest in knowing if they may have GD (two GBA mutations) and other genetic information that could impact their health. Ninety-three-percent of participants were interested in receiving GBA results; however, only 51.6 % of PD participants and 55.6 % of caregivers knew that "scientists have identified genes associated with a higher risk of developing PD." PD patients may benefit from education and genetic counseling on the implications of genetic testing.

Attitudes of patients with cancer about personalized medicine and somatic genetic testing

PURPOSE

Dramatic advances in genomic technology stand to revolutionize cancer care; however, little is known about patients' understanding and acceptance of personalized medicine and widespread genetic testing (GT).

PATIENTS AND METHODS

We conducted a formative, semi-structured interview study with a random sample of patients with lung, colorectal, and breast cancers to assess awareness of personalized medicine and GT and attitudes about somatic GT. Willingness to undergo GT was elicited through hypothetic scenarios.

RESULTS

Sixty-nine patients participated; 71% were women; 42% were black; median age was 59 years; and 42% had an education level ≥ college. We found that a majority of patients either were not aware of the term "personalized medicine" or defined it in unexpected ways. Although many patients identified relevant benefits of somatic testing (eg, informs treatment), many patients also expressed significant concerns (ie, psychological harm and discrimination). A majority of patients expressed a willingness to undergo somatic (predictive, 96%, prognostic, 93%) and germline (cancer risk without incidental information, 87%; cancer risk with incidental information, 81%; pharmacogenetic, 91%) testing; however, far fewer patients expressed a willingness to undergo full genome sequencing (62%). Reluctance was attributed to concerns over incidental findings, information overload, and the lack of a clear benefit.

CONCLUSION

Many patients relayed misunderstandings about somatic testing and a reluctance to undergo full sequencing; oncologists must carefully consider how they present testing to patients so that concerns over discrimination and psychological harm do not hinder test uptake. More work is needed to identify effective ways to communicate complex genomic concepts to patients and research participants.

Attitudes of patients with cancer about personalized medicine and somatic genetic testing

PURPOSE

Dramatic advances in genomic technology stand to revolutionize cancer care; however, little is known about patients' understanding and acceptance of personalized medicine and widespread genetic testing (GT).

PATIENTS AND METHODS

We conducted a formative, semi-structured interview study with a random sample of patients with lung, colorectal, and breast cancers to assess awareness of personalized medicine and GT and attitudes about somatic GT. Willingness to undergo GT was elicited through hypothetic scenarios.

RESULTS

Sixty-nine patients participated; 71% were women; 42% were black; median age was 59 years; and 42% had an education level ≥ college. We found that a majority of patients either were not aware of the term "personalized medicine" or defined it in unexpected ways. Although many patients identified relevant benefits of somatic testing (eg, informs treatment), many patients also expressed significant concerns (ie, psychological harm and discrimination). A majority of patients expressed a willingness to undergo somatic (predictive, 96%, prognostic, 93%) and germline (cancer risk without incidental information, 87%; cancer risk with incidental information, 81%; pharmacogenetic, 91%) testing; however, far fewer patients expressed a willingness to undergo full genome sequencing (62%). Reluctance was attributed to concerns over incidental findings, information overload, and the lack of a clear benefit.

CONCLUSION

Many patients relayed misunderstandings about somatic testing and a reluctance to undergo full sequencing; oncologists must carefully consider how they present testing to patients so that concerns over discrimination and psychological harm do not hinder test uptake. More work is needed to identify effective ways to communicate complex genomic concepts to patients and research participants.