Heritability and shared environmental effects of brain diseases in 12,040 extended families – Nature

Report on the Genetic and Environmental Contributions to Brain Diseases and Alignment with Sustainable Development Goals

1.0 Introduction: Addressing Global Health Challenges

Brain diseases represent a significant global burden, impeding progress towards Sustainable Development Goal 3 (SDG 3): Good Health and Well-being. These non-communicable diseases are leading causes of disability and mortality worldwide. Achieving SDG Target 3.4, which aims to reduce premature mortality from non-communicable diseases, requires a comprehensive understanding of their complex risk factors. This report details a study that investigates the genetic (heritability) and shared environmental contributions to nine common brain diseases. By differentiating these factors, this research provides critical insights for developing targeted prevention and treatment strategies, thereby supporting global public health initiatives and the broader 2030 Agenda for Sustainable Development.

2.0 Study Overview and Methodology

The study utilized a large, population-based cohort to analyze the familial risk of brain diseases, a method that supports robust public health analysis.

• Data Source: Information was collected from 12,040 participants of the Dutch Brain Research Registry, covering a total of 101,379 family members.
• Analysis: Polygenic modeling was employed to estimate heritability (h²) and shared environmental variance (c²) for the nine most prevalent brain diseases. This approach allows for the quantification of genetic versus environmental influences.
• Diseases Studied: The analysis included Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), vascular dementia (VaD), Lewy Body dementia (LBD), ischemic cerebrovascular accident (iCVA), hemorrhagic cerebrovascular accident (hCVA), Parkinson’s disease (PD), and multiple sclerosis (MS).

3.0 Key Findings: Genetic and Environmental Factors

The results highlight the varying degrees to which genetic and environmental factors contribute to different brain diseases, offering a roadmap for tailored public health interventions.

3.1 Heritability Estimates (Genetic Contribution)

A significant genetic component was identified in most brain diseases, underscoring the importance of continued genetic research to develop novel therapies in line with SDG 3.

1. Alzheimer’s Disease (AD): 73%
2. Amyotrophic Lateral Sclerosis (ALS): 72%
3. Frontotemporal Dementia (FTD): 48%
4. Vascular Dementia (VaD): 41%
5. Parkinson’s Disease (PD): 38%
6. Lewy Body Dementia (LBD): 34%
7. Hemorrhagic CVA (hCVA): 29%
8. Ischemic CVA (iCVA): 27%
9. Multiple Sclerosis (MS): 10%

3.2 Shared Environmental Effects

The study identified a notable contribution from shared environmental factors, particularly in vascular-related conditions. This finding is crucial for public health policy, as it points towards modifiable risks that can be addressed to promote community health, aligning with SDG 3 and SDG 11 (Sustainable Cities and Communities).

• Ischemic CVA (iCVA): 15.9%
• Hemorrhagic CVA (hCVA): 14.9%
• Frontotemporal Dementia (FTD): 9.7%
• Vascular Dementia (VaD): 9.0%
• Parkinson’s Disease (PD): 7.5%
• Alzheimer’s Disease (AD): 5.8%

Note: Shared environmental effects could not be estimated for LBD, MS, and ALS due to the limited number of cases.

4.0 Discussion: Implications for Sustainable Development Goals

The findings provide a dual pathway for action that directly supports the achievement of the Sustainable Development Goals.

4.1 Advancing SDG 3: Good Health and Well-being

The strong heritability estimates for diseases like AD and ALS reinforce the need for investment in genetic research to identify therapeutic targets. Simultaneously, the significant shared environmental effects in AD, VaD, and stroke highlight the critical importance of prevention. These environmental factors often relate to modifiable risks such as diet, lifestyle, and exposure to pollution. Public health initiatives aimed at mitigating these risks are essential for achieving SDG Target 3.4 by preventing premature death and promoting mental health and well-being.

4.2 Promoting SDG 11: Sustainable Cities and Communities

The influence of shared environments on vascular-related brain diseases underscores the connection between health and living conditions. Factors such as air quality, access to healthy food, and safe environments for physical activity are shared at a household or community level. By addressing these modifiable risk factors, policymakers can create healthier urban and rural environments. This directly contributes to SDG Target 11.6, which calls for reducing the adverse per capita environmental impact of cities, including air quality. Promoting healthier communities is a cornerstone of sustainable development and disease prevention.

5.0 Conclusion

This study confirms that brain diseases arise from a complex interplay of genetic and environmental factors. The high heritability of certain conditions necessitates continued focus on genetic and biomedical research. However, the robust influence of shared environmental factors, especially in vascular-related diseases, presents a clear opportunity for impactful public health interventions. By addressing modifiable environmental and lifestyle risks, nations can make significant strides toward achieving SDG 3 (Good Health and Well-being) and SDG 11 (Sustainable Cities and Communities), ultimately fostering healthier populations and more sustainable living environments for all.

Analysis of Sustainable Development Goals (SDGs) in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

The article on the heritability and environmental effects of brain diseases connects to several Sustainable Development Goals (SDGs). The primary focus on health and disease directly aligns with SDG 3, while its emphasis on scientific research and environmental risk factors links to SDG 9 and SDG 11, respectively.

• SDG 3: Good Health and Well-being

  This is the most relevant SDG. The article’s entire focus is on understanding the causes of major brain diseases such as Alzheimer’s, Parkinson’s, and stroke, which it identifies as “among the leading causes of death and disability worldwide.” By investigating genetic and environmental risk factors, the research aims to inform “more effective prevention strategies” and “improve prevention and treatment,” which is central to ensuring healthy lives and promoting well-being for all at all ages.

• SDG 9: Industry, Innovation, and Infrastructure

  The study itself represents an advancement in scientific research and innovation. The article describes using a large-scale, population-based “Dutch Brain Research Registry,” advanced statistical methods (“polygenic modeling in SOLAR”), and a large dataset (“101,379 individuals”) to generate new knowledge. This work contributes to enhancing scientific research capabilities, a key aspect of SDG 9, which seeks to foster innovation and support scientific discovery to address global challenges like public health.

• SDG 11: Sustainable Cities and Communities

  The article highlights the role of “shared environmental factors” in the development of brain diseases. It explicitly mentions “air pollution, pesticides, and heavy metals” as “preventable risks factors.” This connects the incidence of neurodegenerative diseases to environmental quality, which is a core concern of SDG 11. The findings that shared environments contribute to diseases like stroke and Alzheimer’s underscore the importance of public health policies aimed at reducing environmental hazards in human settlements.

2. What specific targets under those SDGs can be identified based on the article’s content?

Based on the article’s focus, the following specific SDG targets can be identified:

1. Target 3.4: Reduce premature mortality from non-communicable diseases

   The article directly addresses this target by focusing on non-communicable brain diseases (NCDs) like dementia, stroke, and Parkinson’s disease. It states that these are “leading causes of death and disability.” The research goal is to “improve prevention and treatment” by understanding their root causes. The discussion on “mitigate modifiable risk factors” is a direct call for prevention, which is the cornerstone of Target 3.4, aiming to reduce premature mortality from NCDs by one-third by 2030.

2. Target 9.5: Enhance scientific research and encourage innovation

   This study is a clear example of the activity described in Target 9.5. The research uses a “large extended family design” and advanced software (“SOLAR-Eclipse”) to “estimate heritability and shared environmental variance” for nine brain diseases. The acknowledgements section lists multiple national research funding organizations (e.g., NWO, ZonMW), indicating investment in research and development. The entire paper is an output of enhanced scientific research aimed at solving a major health problem.

3. Target 11.6: Reduce the adverse environmental impact of cities

   The article’s finding of a “robust shared environmental effect in vascular-related brain diseases” directly supports the rationale behind Target 11.6. It identifies “air pollution” as a key environmental exposure that can be a “preventable risk factor.” By demonstrating a statistical link between shared environments and disease prevalence (e.g., “iCVA showed the highest shared environmental effect of 15.9%”), the study provides scientific evidence for why public health initiatives should focus on improving environmental quality, particularly air quality in populated areas, to reduce disease incidence.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

The article mentions and implies several indicators that can measure progress towards the identified targets.

• Indicators for Target 3.4

  • Mortality and Prevalence Rates of NCDs: The article implicitly refers to Indicator 3.4.1 (Mortality rate attributed to cardiovascular disease, cancer, diabetes or chronic respiratory disease) by stating that brain diseases, including stroke (a cardiovascular event), are “among the leading causes of death.” It provides specific prevalence data from its cohort, such as “AD was the most frequently reported condition, affecting 8,149 individuals (8.0% of cohort).” Tracking these rates is a direct measure of the burden of NCDs.
  • Quantification of Risk Factors: The study’s primary metrics, heritability (h²) and shared environmental variance (c²), serve as specific, measurable indicators of the genetic and environmental burden of disease. For example, it reports “heritability of AD… was estimated to be 72.8%” and the “shared environmental effect” for iCVA was “15.9%.” These metrics help quantify the impact of modifiable (environmental) versus non-modifiable (genetic) risks, which is crucial for designing prevention strategies.

• Indicators for Target 9.5

  • Research Output: The publication of this scientific paper itself is an indicator of progress in scientific research.
  • Investment in R&D: While not providing specific figures (as in Indicator 9.5.1: Research and development expenditure as a proportion of GDP), the acknowledgements section lists numerous funding bodies (“NWO,” “ZonMW,” “Health~Holland”), implying significant public and private investment in this area of research.
  • Research Infrastructure: The use of the “Dutch Brain Research Registry” with over 12,000 participants and the “Snellius supercomputer” are indicators of the advanced infrastructure and technological capability being used to conduct this research.

• Indicators for Target 11.6

  • Impact of Environmental Factors: The “shared environmental effect” (c²) calculated for diseases like AD (5.8%), VaD (9.0%), and stroke (iCVA 15.9%, hCVA 14.9%) serves as a direct indicator of the health impact of shared environmental conditions, which include air quality. This provides a scientific basis for linking environmental quality indicators (like Indicator 11.6.2: Annual mean levels of fine particulate matter) to health outcomes, thereby measuring the effectiveness of policies aimed at reducing the adverse environmental impact of cities.

4. Create a table with three columns titled ‘SDGs, Targets and Indicators” to present the findings from analyzing the article.

Source: nature.com