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

Predicting age of onset and progression of disease in late-onset genetic neurodegenerative diseases: An ethics review and research agenda

Currently, a prognostic biomarker-based model is being developed to predict the onset and disease progression of Huntington's Disease (HD) and Spinocerebellar Ataxia (SCA) types 1 and 3, both late-onset genetic neurodegenerative diseases lacking a disease-modifying treatment (DMT). The need for more accurate predictions of onset and disease progression arises in the context of clinical trials evaluating the effectiveness of potential DMTs and identifying the optimal time to initiate such a DMT. Moreover, such a prognostic model may provide mutation carriers with personal utility. The aim of this article is to anticipate the ethical issues raised by these new prognostic models and to formulate the ethical issues that need to be addressed to facilitate an ethically responsible development and implementation of such a model. Part one of this article describes the ethical issues raised by presymptomatic genetic testing for HD and evaluates whether and how these issues may also occur by predicting onset and disease progression. Part two presents the results of a critical interpretative review into the ethical issues raised by biomarker testing in other late-onset neurodegenerative diseases lacking a DMT. The review aims to identify new ethical issues related to biomarker testing for predicting the onset and disease progression of HD and SCA. Finally, based on parts one and two, part three proposes a research agenda for the near future regarding the most pressing ethical issues that need to be addressed to ensure an ethically responsible implementation of such a prognostic model in both research settings and clinical practice.

Artificial intelligence in Parkinson's disease: Early detection and diagnostic advancements

Parkinson's disease (PD) is the second most common neurodegenerative disorder, globally affecting men and women at an exponentially growing rate, with currently no cure. Disease progression starts when dopaminergic neurons begin to die. In PD, the loss of neurotransmitter, dopamine is responsible for the overall communication of neural cells throughout the body. Clinical symptoms of PD are slowness of movement, involuntary muscular contractions, speech & writing changes, lessened automatic movement, and chronic tremors in the body. PD occurs in both familial and sporadic forms and modifiable and non-modifiable risk factors and socioeconomic conditions cause PD. Early detectable diagnostics and treatments have been developed in the last several decades. However, we still do not have precise early detectable biomarkers and therapeutic agents/drugs that prevent and/or delay the disease process. Recently, artificial intelligence (AI) science and machine learning tools have been promising in identifying early detectable markers with a greater rate of accuracy compared to past forms of treatment and diagnostic processes. Artificial intelligence refers to the intelligence exhibited by machines or software, distinct from the intelligence observed in humans that is based on neural networks in a form and can be used to diagnose the longevity and disease severity of disease. The term Machine Learning or Neural Networks is a blanket term used to identify an emerging technology that is created to work in the way of a "human brain" using many intertwined neurons to achieve the same level of raw intelligence as that of a brain. These processes have been used for neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease, to assess the severity of the patient's condition. In the current article, we discuss the prevalence and incidence of PD, and currently available diagnostic biomarkers and therapeutic strategies. We also highlighted currently available artificial intelligence science and machine learning tools and their applications to detect disease and develop therapeutic interventions.

Taking the risk. A systematic review of ethical reasons and moral arguments in the clinical use of polygenic risk scores

Debates about the prospective clinical use of polygenic risk scores (PRS) have grown considerably in the last years. The potential benefits of PRS to improve patient care at individual and population levels have been extensively underlined. Nonetheless, the use of PRS in clinical contexts presents a number of unresolved ethical challenges and consequent normative gaps that hinder their optimal implementation. Here, we conducted a systematic review of reasons of the normative literature discussing ethical issues and moral arguments related to the use of PRS for the prevention and treatment of common complex diseases. In total, we have included and analyzed 34 records, spanning from 2013 to 2023. The findings have been organized in three major themes: in the first theme, we consider the potential harms of PRS to individuals and their kin. In the theme "Threats to health equity," we consider ethical concerns of social relevance, with a focus on justice issues. Finally, the theme "Towards best practices" collects a series of research priorities and provisional recommendations to be considered for an optimal clinical translation of PRS. We conclude that the use of PRS in clinical care reinvigorates old debates in matters of health justice; however, open questions, regarding best practices in clinical counseling, suggest that the ethical considerations applicable in monogenic settings will not be sufficient to face PRS emerging challenges.

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.

Ethical, legal, and social implications of genetic risk prediction for multifactorial disease: a narrative review identifying concerns about interpretation and use of polygenic scores

Advances in genomics have enabled the development of polygenic scores (PGS), sometimes called polygenic risk scores, in the context of multifactorial diseases and disorders such as cancer, cardiovascular disease, and schizophrenia. PGS estimate an individual's genetic predisposition, as compared to other members of a population, for conditions which are influenced by both genetic and environmental factors. There is significant interest in using genetic risk prediction afforded through PGS in public health, clinical care, and research settings, yet many acknowledge the need to thoughtfully consider and address ethical, legal, and social implications (ELSI). To contribute to this effort, this paper reports on a narrative review of the literature, with the aim of identifying and categorizing ELSI relating to genetic risk prediction in the context of multifactorial disease, which have been raised by scholars in the field. Ninety-two articles, spanning from 1977 to 2021, met the inclusion criteria for this study. Identified ELSI included potential benefits, challenges and risks that focused on concerns about interpretation and use, and ethical obligations to maximize benefits, minimize risks, promote justice, and support autonomy. This research will support geneticists, clinicians, genetic counselors, patients, patient advocates, and policymakers in recognizing and addressing ethical concerns associated with PGS; it will also guide future empirical and normative research.

Psychosocial Impact of Huntington's Disease and Incentives to Improve Care for Affected Families in the Underserved Region of the Slovak Republic

INTRODUCTION

Huntington's disease (HD) is often on the margin of standard medical practice due to its low prevalence, the lack of causal treatment, and the typically long premanifest window prior to the onset of the symptoms, which contrasts with the long-lasting burden that the disease causes in affected families.

METHODS

To capture these socio-psychological aspects of HD and map the experiences of affected individuals, persons at risk of HD, and caregivers, we created a questionnaire using a qualitative research approach. The questionnaire containing 16 questions was conducted online for a period of three months through patient associations in Slovakia and their infrastructures.

RESULTS

In total, we received 30 responses. The survey results, in particular, indicate insufficient counselling by physicians with explicitly missing information about the possibility of preimplantation genetic diagnostic. There was also a necessity to improve comprehensive social and health care in the later stages of the disease, raise awareness of the disease in the general health community, and provide more information on ongoing clinical trials.

CONCLUSION

The psychosocial effects, as well as the burden, can be mitigated by comprehensive genetic counselling as well as reproductive and financial guidelines and subsequent therapeutic programs to actively support patients, caregivers, children, and adolescents growing up in affected families, preferably with the help of local HD community association.

LIMITATIONS

We have used online data collection to reach a wider HD community, but at the same time, we are aware that the quality of the data we would obtain through face-to-face interviews would be considerably better. Therefore, future studies need to be conducted to obtain more detailed information.

Glymphatic System: Emerging Therapeutic Target for Neurological Diseases

The newly discovered glymphatic system acts as pseudolymphatic vessels subserving brain waste clearance and is functionally dependent on astrocytic aquaporin-4 channels. The glymphatic system primarily functions during sleep as an interchange between cerebrospinal fluid and interstitial fluid, with cerebrospinal fluid flowing into the parenchyma via the perivascular spaces and then exchanging with interstitial fluid. The discovery of meningeal lymphatics helps refine the conceptual framework of glymphatic pathway, as certain waste products collected alongside perivascular spaces ultimately drain into the cervical lymph nodes via meningeal lymphatics, whose function regulates the functioning of the glymphatic system. The glymphatic and meningeal lymphatic systems are critical for the homeostasis of central nervous system, and their malfunctions complicate cerebral dysfunction and diseases. The present review will shed light on the structure, regulation, functions, and interrelationships of the glymphatic system and meningeal lymphatics. We will also expound on their impairments and corresponding targeted intervention in neurodegenerative diseases, traumatic brain injury, stroke, and infectious/autoimmune diseases, offering valuable references for future research.

Giving Body to the Body: Predictive Genetic Testing and Self-desomatization

Genetics test in predictive medicine seems to take charge of the uniqueness of any human being. Unlike preventive medicine it moves from the theoretical assumption of the knowledge of a specific individual’s genetic structure and potential fragility. However, the attention paid to the gene risks placing the living and experienced body in the shadow. Sometimes, “genetic news” can make the subject in the present act like a sick person without being so, read every event in that direction, and, ultimately, fulfill the prophecy. The article goes beyond the alleged non-exceptionalism of genetic data and discusses the symbolic value that the gene has assumed and its role in reflexivity and self-perception.

Ethical Aspects of Genotype Disclosure: Perceptions of Participants in a Nutrigenetic Study in Finland

OBJECTIVE

The aim of this study was to gain insight into the understanding of genetics and perceptions on the ethical issues related to genotype disclosure of the participants in a nutrigenetic study.

METHODS

A close-ended questionnaire was developed based on literature and discussions among the research group members. The questionnaire contained a -total of 33 questions, which were divided into 4 categories - demographics, knowledge assessment, concerns related to participation, and opinions on disclosure of information. Majority of the participants (250 out of 281) of a nutrigenetic study, in which effect of disclosing APOE allele status on lifestyle changes was studied, completed the questionnaire online following the informed consent process. The responses from the knowledge assessment and the concern categories were transformed into knowledge and concern scales, respectively, and analysed by descriptive statistical methods. The statistical associations between the categorical variables were determined using χ2 test of independence. The relationship between the continuous variables was assessed using Pearson product-moment correlation coefficient and internal consistency of questions by Cronbach's alpha.

RESULTS

No correlation was observed between the level of education and knowledge scores. About 10% of the participants thought that the genetic predisposition would be stressful to them and their family members.

CONCLUSIONS

Careful distribution of information before a nutrigenetic study supports understanding and reduces concerns of genetic susceptibility. In Finland, strong basic education is likely to have strengthened the trust in research process.

Genetic Variation Associated With Depressive Symptoms in Breast Cancer Patients: A Systematic Review

BACKGROUND

Depressive symptoms are highly prevalent in breast cancer patients. These symptoms can contribute to lower treatment adherence, increased healthcare charges, and higher mortality rates. Growing evidence suggests that genetic variations may be associated with depressive symptom susceptibility.

OBJECTIVE

To comprehensively review current findings on the association of genetic variations with depressive symptoms in breast cancer patients.

METHODS

A literature search was conducted using keywords such as gene variation, single-nucleotide polymorphism, depression/depressive symptoms, and breast cancer. Four hundred articles were retrieved from PubMed, Web of Science, CINAHL, and PsycINFO, yielding 9 full-text, data-based articles. The study quality was assessed using the STrengthening the REporting of Genetic Association studies guideline.

RESULTS

Genetic polymorphisms in brain-derived neurotrophic factor (BDNF), interferon γ receptor 1 (IFNGR1), interleukin-6 (IL-6), tumor necrosis factor α (TNFA), and IL-1B were found to be associated with depressive symptoms among breast cancer patients. The role of serotonin transporter gene linked promotor region (5-HTTLPR) functional polymorphisms on depressive symptoms was inconclusive. The overall quality of reporting results and methods was medium.

CONCLUSIONS

This is the first review of genetic variations related to differences in levels of depressive symptoms among breast cancer patients. Genetic polymorphisms in inflammatory, neuronal system, and signal transduction pathways can influence the susceptibility. However, more research regarding this topic is needed to further clarify genetic risk factors.

IMPLICATIONS FOR PRACTICE

Healthcare providers may determine patients at higher risk of developing depression and symptom outcomes if genetic biomarkers with good sensitivity/specificity are provided. This knowledge can potentially help the development of personalized treatment and decision making for those patients.