Target Audience
- Researchers, healthcare professionals, and anyone interested in large-scale biobanks and cohort studies, including UK Biobank and the Tohoku Medical Megabank Project (ToMMo).
- Professionals working in genomic medicine, personalized prevention, multi-omics analysis, and the use of healthcare data in research and industry.
- Readers who want to understand how Japan's medical research infrastructure has developed, the challenges it faces, and its potential for real-world healthcare applications.
Executive Summary
- The Tohoku Medical Megabank Project (TMM Project) was conceived in response to the 2011 Great East Japan Earthquake. Since then, it has evolved from a medical recovery initiative into a nationally important research infrastructure supporting genomic medicine and personalized prevention in Japan.
- The project has established a cohort of approximately 150,000 participants, primarily in Miyagi and Iwate Prefectures, collecting health information, biological samples, and genomic and omics data. One of its most distinctive features is a three-generation cohort that follows children and their families from pregnancy onward.
- Compared with UK Biobank, ToMMo has particular strengths in multigenerational family information, genomic characteristics of Japanese populations, detailed health examinations, and returning health information to research participants.
- Beginning in fiscal year 2026, the project entered its fourth phase, focusing on expanding research access, linking genomic data with medical records, and applying research findings to personalized healthcare.
- Its major challenges now include maintaining long-term follow-up, improving data accessibility, demonstrating measurable benefits from research, and securing sustainable funding. The project's emphasis is shifting from building a large-scale research resource to translating that resource into tangible benefits for healthcare, disease prevention, and society.
1. What Is the Tohoku Medical Megabank Project (ToMMo)?
1.1 A National Research Project Born from Disaster Recovery
The Tohoku Medical Megabank Project (TMM Project) is a large-scale medical research initiative conceived in response to the Great East Japan Earthquake of March 2011.
The project is led by two institutions: the Tohoku Medical Megabank Organization (ToMMo) at Tohoku University and the Iwate Tohoku Medical Megabank Organization (IMM) at Iwate Medical University.
Together, they have conducted long-term health studies of local residents while building a genomic research infrastructure to support next-generation medicine.[1]
The project has two major objectives.
The first is to support the health of residents in earthquake-affected communities and contribute to the restoration of regional healthcare systems.
The second is to collect and analyze health information, biological samples, genomic data, and related information over extended periods, creating a research foundation for personalized medicine and personalized disease prevention.
In other words, ToMMo is not simply a project for collecting genomic data.
It was conceived with two complementary missions: a social mission to protect the health of local communities and a scientific mission to advance the future of medicine.
1.2 Basic Facts About ToMMo
| Item | Description |
|---|---|
| Project name | Tohoku Medical Megabank Project (TMM Project) |
| Main institutions | Tohoku Medical Megabank Organization (ToMMo), Tohoku University; Iwate Tohoku Medical Megabank Organization (IMM), Iwate Medical University |
| Origin | Great East Japan Earthquake of 2011 |
| ToMMo established | February 1, 2012 |
| IMM established | July 1, 2012 |
| Main study regions | Miyagi and Iwate Prefectures |
| Cohort size | Approximately 150,000 participants |
| Main research areas | Lifestyle, diseases, genomics, omics, environmental factors, family relationships, and intergenerational health |
| Project phase in FY2026 | Phase 4 |
Sources: ToMMo's official history and AMED project materials.[1][3]
1.3 Similarities to UK Biobank
One of the most relevant international comparisons for ToMMo is UK Biobank.
UK Biobank is a large-scale research infrastructure that has collected health information, lifestyle data, genetic information, and biological samples from approximately 500,000 participants, following their health outcomes over time.[5]
ToMMo shares several fundamental characteristics with UK Biobank.
Both are population-based longitudinal research resources that collect health information, biological samples, and genomic data, making these resources available for a broad range of scientific investigations.
However, the differences between them extend beyond their respective participant numbers.
ToMMo originated from a disaster recovery initiative and places particular emphasis on three-generation family information, the genomic characteristics of Japanese populations, and the return of health information to participants.
These characteristics distinguish its scientific design and operational philosophy from those of UK Biobank.
2. How Was ToMMo Conceived and Established?
2.1 The Great East Japan Earthquake as the Starting Point
The Great East Japan Earthquake on March 11, 2011, caused devastating damage to healthcare systems in Miyagi and Iwate Prefectures.
Affected communities faced numerous challenges, including:
- Destruction of healthcare facilities
- Shortages of healthcare professionals
- Evacuation and relocation of residents
- Disruption of ongoing management for chronic diseases
- The need for long-term health support for disaster-affected populations
In response, Tohoku University and its partners began developing a concept that would go beyond short-term healthcare restoration.
The idea was to combine long-term health monitoring of local residents with the construction of a research infrastructure for next-generation medicine.
Two developments were particularly important in turning this concept into a national project.
On June 11, 2011, the Governor of Miyagi Prefecture proposed the realization of a medical megabank initiative at the Reconstruction Design Council in Response to the Great East Japan Earthquake, emphasizing its importance for rebuilding regional healthcare.
Five days later, on June 16, Masayuki Yamamoto, then Dean of the Tohoku University Graduate School of Medicine, presented the concept at the second Medical Innovation Council meeting.[1]
The convergence of regional reconstruction policy and an ambitious university-led medical research vision was a crucial factor in the establishment of ToMMo.
2.2 Timeline: From 2011 to 2026
The following timeline summarizes the major milestones in ToMMo's development.
| Period | Major developments | Significance |
|---|---|---|
| 2011 | The Great East Japan Earthquake occurred. The medical megabank concept took shape in June. Funding was included in Japan's third supplementary budget, enacted on November 21. | Established and funded as a disaster reconstruction initiative |
| 2012 | ToMMo was established at Tohoku University on February 1, followed by IMM at Iwate Medical University on July 1. The overall project plan was developed following discussions led by the Ministry of Education, Culture, Sports, Science and Technology (MEXT). | Established the institutional framework |
| 2013–2017 | Participant recruitment and baseline surveys were conducted for the Community-Based Cohort and the Birth and Three-Generation Cohort. | Created a research resource of approximately 150,000 participants |
| 2015–2016 | Oversight transitioned to the Japan Agency for Medical Research and Development (AMED) in FY2015. The project surpassed its target of 150,000 participants in 2016. Secure remote-access facilities were also developed. | Strengthened the project as a national research infrastructure |
| 2017–2020 | Phase 2 focused on cohort follow-up, integrated genomic and omics analysis, and wider sharing of samples and data. The direction for continued development was clarified in 2020. | Shifted from data collection toward utilization |
| 2021–2025 | Phase 3 emphasized maintaining and enhancing research resources, long-term follow-up, data and sample utilization, returning information to participants, and real-world implementation. | Advanced applications in personalized healthcare |
| 2026 onward | Phase 4 began. Access to whole-genome data was expanded, and the long-term sustainability of the research infrastructure became an important policy consideration. | Emphasized sustainable utilization and societal benefits |
Sources: ToMMo's official history, AMED project materials, and Tohoku University's April 2026 announcement.[1][3][4]
2.3 How the Project's Objectives Have Evolved
ToMMo's development can be understood in terms of three broad stages.
The first stage focused on the health recovery of disaster-affected communities.
Understanding the health status of residents and responding to health challenges following the earthquake were central objectives.
The second stage focused on building Japan's genomic and biobank research infrastructure.
The project established a cohort of approximately 150,000 participants and accumulated health information, biological samples, and genomic and omics data.
It also developed systems to make these resources available for medical research.
The third stage emphasizes sustained research utilization and benefits for society.
Maintaining long-term follow-up remains essential, but increasing importance is being placed on making data available to researchers and companies and translating scientific findings into disease prevention, diagnosis, and treatment.
Thus, while ToMMo began as a disaster recovery initiative, it has become an important public research infrastructure supporting genomic medicine in Japan.
3. Key Characteristics of ToMMo's Research Infrastructure
3.1 Two Complementary Cohorts
The research infrastructure of ToMMo is built around two large-scale cohorts with different research objectives.
The Community-Based Cohort (TMM CommCohort)
The Community-Based Cohort mainly studies adult residents of Miyagi and Iwate Prefectures.
It includes approximately 84,000 participants, consisting of around 52,000 from Miyagi and 32,000 from Iwate.
The study collects information on lifestyle, medical history, physical measurements, blood tests, and genetic characteristics, following participants over extended periods to examine disease development and changes in health status.
Major research areas include:
- Cancer
- Cardiovascular diseases
- Diabetes
- Dementia
Researchers investigate how genetic factors and living environments influence these conditions, with the ultimate goal of contributing to disease prevention.
The Birth and Three-Generation Cohort (TMM BirThree Cohort)
The Birth and Three-Generation Cohort follows children and their families beginning during pregnancy.
It is a family-based cohort involving approximately 73,000 participants, centered on newborns and their relatives.
The study links health and genetic information from pregnant women, children, fathers, grandparents, siblings, and other family members.
Major research topics include:
- Child growth and development
- Allergic diseases
- The early-life origins of lifestyle-related diseases
- Intergenerational relationships between genetic and environmental factors
The approximately 73,000 figure represents the scale of the newborn-centered family cohort and should not simply be added to the overall participant count.
These figures are based on cohort information published in March 2025.[1]
3.2 The Scientific Value of the Three-Generation Cohort
The three-generation cohort is one of ToMMo's most distinctive scientific strengths.
Because family relationships are known, researchers can compare genomic information and health outcomes among biologically related individuals.
This makes it possible to investigate questions that are difficult to address using cohorts primarily composed of unrelated adults.
For example, when studying a child's health, researchers can simultaneously consider:
- The child's own genetic characteristics
- The maternal environment during pregnancy
- Lifestyle factors shared within the family
- Genetic influences inherited across generations
This structure allows researchers to examine how genetic and environmental factors interact to influence health across generations.
It is particularly valuable for studying child development, allergic diseases, and the early origins of lifestyle-related conditions.
Although UK Biobank contains information about familial relationships, recruiting three generations of family members is not a central element of its original study design.
The three-generation cohort is therefore an important feature distinguishing ToMMo from UK Biobank.
3.3 A Multi-Omics Research Platform, Not Just a Genomic Database
ToMMo collects detailed health information and biological samples, which are subjected to a wide range of analyses.
The collected information includes lifestyle data, medical history, blood and urine samples, physical examinations, and brain MRI data.
In addition to genomics, the project conducts multi-omics analyses that combine information from different types of biological molecules.
| Data type | Main information |
|---|---|
| Genomics | DNA sequences and genetic variants |
| Metabolomics | Metabolites and their relationships with nutrition and environmental exposures |
| Proteomics | Protein abundance and changes |
| Other omics | Epigenomics, microbiome data, and related information |
| Health and lifestyle data | Lifestyle factors, medical history, health examination results, and physical measurements |
Integrating these datasets allows researchers to investigate relationships among genetic factors, environmental influences, changes over time, and disease development.
According to a report submitted by Tohoku University to MEXT in August 2026, the project had achieved the following milestones.[2]
| Indicator | Achievement |
|---|---|
| Completed whole-genome analyses | Approximately 120,000 individuals |
| SNP array analyses | Approximately 150,000 individuals |
| Cumulative number of stored samples | Approximately 4.7 million tubes (as of March 2026) |
| Publicly released metabolomics information | More than 79,000 samples |
These figures illustrate the scale of ToMMo's biological sample collections and its genomic and multi-omics research capabilities.
However, the number of individuals whose whole genomes have been analyzed should not be confused with the number of datasets currently available to external researchers.
3.4 Returning Health and Genetic Information to Participants
In many conventional research biobanks, participants have limited opportunities to receive their individual research findings.
ToMMo takes a somewhat different approach.
Returning health examination results to participants has been an important component of the project.
It has also developed programs for returning clinically significant genetic findings to research participants.
According to the August 2026 report, genetic findings were returned to 97 individuals carrying pathogenic variants associated with hereditary breast and ovarian cancer syndrome or Lynch syndrome.
Of these individuals, 78 visited medical institutions and began examinations or follow-up care aimed at early disease detection.[2]
This represents an important example of connecting genomic research with concrete health-related actions and medical interventions, rather than limiting genomic information to scientific analysis.
Nevertheless, returning genetic findings requires careful consideration.
Important requirements include:
- Clinical validity of the genetic findings being returned
- Genetic counseling
- The participant's preferences regarding receiving the information
- Appropriate medical follow-up after results are returned
It is also important to recognize that ToMMo does not return all genomic findings to every participant.
3.5 A Public Research Infrastructure Accessible to Industry
ToMMo is not a closed database available only to researchers within the participating institutions.
Subject to research review and approval, external universities, research organizations, and companies can access data and biological samples.
As of the end of March 2026, the cumulative figures for the Tohoku University component included 160 approved data or sample distribution projects and 433 approved collaborative research projects.[2]
Furthermore, in April 2026, the number of individuals whose whole-genome data were available for distribution increased from approximately 15,000 to approximately 69,000.[4]
External access requires research review and contractual arrangements.
For highly sensitive genomic information, researchers must also use secure analysis environments.
When evaluating the scale and accessibility of a research infrastructure, several indicators must be distinguished.
| Indicator | Meaning |
|---|---|
| Cohort participants | Individuals who consented to participate in the study |
| Completed genomic analyses | Individuals whose genomic analyses have been completed |
| Available datasets | Data accessible to external researchers under applicable review and contractual conditions |
| Actual research utilization | Number of research projects that have used the data |
For example, even if whole-genome analysis has been completed for approximately 120,000 individuals, this does not mean that all those datasets are simultaneously accessible to external researchers under identical conditions.
Evaluating the value of a biobank therefore requires looking beyond the amount of data collected to examine how much of it can actually be used and how extensively it contributes to research.
4. Comparing ToMMo with UK Biobank
4.1 Similarities and Differences in Research Design
Both UK Biobank and ToMMo are research infrastructures based on prospective population cohorts.
However, they differ in participant populations, research design, data characteristics, and access arrangements.[1][5]
| Comparison | UK Biobank | ToMMo / TMM Project |
|---|---|---|
| Original objective | Research on the prevention, diagnosis, and treatment of a broad range of diseases | Disaster recovery and next-generation medicine |
| Participant population | Approximately 500,000 | Approximately 150,000 |
| Participants at recruitment | Adults aged 40–69 | Adults, pregnant women, children, and families |
| Geographic coverage | Broad coverage across the United Kingdom | Primarily Miyagi and Iwate Prefectures |
| Family information | Includes familial relationships, but three-generation recruitment is not central | Three-generation cohort is a defining feature |
| Genomic research | Large-scale genomic analysis infrastructure | Genomic research focused on Japanese populations |
| Medical record linkage | Strong integration with NHS and related health records | Expanding linkage with health examinations, public records, and healthcare providers |
| External research access | Available to international researchers through secure research environments | Primarily supports academic and industry researchers in Japan through data distribution and collaboration |
| Participant feedback | Emphasis on participants' contribution to research | Active return of health examination results and selected genetic findings |
4.2 Why Participant Numbers Alone Do Not Determine Research Value
UK Biobank includes approximately 500,000 participants, compared with approximately 150,000 in ToMMo.
However, the value of a research infrastructure cannot be evaluated solely by the number of participants.
UK Biobank is particularly well suited to research on diverse diseases and health outcomes using its large sample size and extensive linkage with medical records.
ToMMo, on the other hand, has distinctive strengths in:
- Life-course research from pregnancy and birth through adolescence
- Three-generation family relationships
- Genomic characteristics of Japanese populations
- Repeated, detailed health examinations
- Interactions between genetic factors and environmental exposures
These differences suggest that the two research infrastructures should be regarded as complementary rather than competing resources.
UK Biobank can be characterized as a large-scale research platform for investigating diseases across broad adult populations, while ToMMo offers a particularly detailed research platform integrating family relationships, generations, and environmental information.
5. Current Challenges Facing ToMMo
ToMMo has established a cohort of approximately 150,000 participants and accumulated extensive genomic and multi-omics data.
However, maintaining and developing this infrastructure over the long term involves several challenges.
The following discussion draws primarily on AMED's FY2025 post-project evaluations and materials submitted to MEXT in August 2026.[2][3]
It is important to distinguish between challenges explicitly identified in external evaluations and broader issues arising from the characteristics of the research infrastructure.
5.1 Challenge 1: Maintaining Long-Term Participation and Follow-Up Rates
In longitudinal cohort studies, the value of the data increases when participants continue contributing information over many years.
However, continued participation becomes more difficult over time because of factors such as:
- Relocation
- Aging
- Changes in health status
- The burden of repeated surveys and examinations
AMED's FY2025 evaluation of the Iwate Medical University component explicitly noted declining numbers of survey participants and decreasing response rates to mailed questionnaires.
It also called for measures to address regions and age groups where participation has become more difficult.[3]
This problem has two important dimensions.
First, as the number of participants who can be followed decreases, the statistical precision of analyses may decline.
Second, if the likelihood of dropping out differs according to health status or living environment, the resulting data may become systematically biased.
Beginning in FY2026, ToMMo has been pursuing several responses, including:
- Following older participants through public administrative information
- Reorganizing examination facilities
- Conducting surveys focused on adolescents
- Adjusting follow-up methods according to participants' life stages
Maintaining the quality of long-term follow-up will be essential to preserving the value of the research infrastructure.[2]
5.2 Challenge 2: Enriching the Data and Linking It with Medical Records
Even a very large whole-genome dataset has limitations if it cannot be reliably connected with information on disease incidence, diagnosis, and treatment.
ToMMo is therefore expanding linkages with:
- Health examination records
- Medical claims data
- Disease registries
- Long-term care insurance information
- Clinical records from healthcare institutions
According to the August 2026 report, medical information had been collected for approximately 7,000 participants whose records had been matched with Tohoku University Hospital.[2]
This represents important progress.
At the same time, relative to the overall cohort of approximately 150,000 participants, it illustrates the potential for further expansion of medical record linkage.
In UK Biobank, linkage with NHS medical records is a central element of the research infrastructure.
For ToMMo, the coverage, quality, and frequency of updates to linked medical records are also likely to play a major role in determining its long-term scientific value.
5.3 Challenge 3: Expanding Access for External Researchers and Companies
ToMMo is transitioning from a stage primarily focused on accumulating data to one that emphasizes making those data easier to use.
External research access involves multiple procedures and technical requirements, including:
- Review of research proposals
- Contractual arrangements
- Identification and selection of appropriate datasets
- Access to secure computing environments
In its Phase 4 plans, ToMMo has identified several areas for improvement, including data access support, better analysis environments, and opportunities for researchers to inspect relevant data before formally starting their research.[2]
The project has also indicated a target of approximately 300 research uses through a combination of data distribution and collaborative research, including projects conducted independently by companies.
This suggests that reducing the time and effort required for researchers to begin using the data is becoming increasingly important, alongside the volume and diversity of the available resources.
A large collection of research data cannot realize its full potential unless researchers can use it effectively.
5.4 Challenge 4: Translating Research Findings into Real-World Benefits
In its FY2025 evaluation, AMED called on the Tohoku University component to define clear key performance indicators (KPIs) for societal implementation and establish quantitative targets.[3]
This indicates that scientific publications and the amount of data collected are no longer sufficient as the only measures of success.
It is becoming increasingly important to demonstrate how research findings contribute to actual healthcare and disease prevention.
Potential evaluation indicators include:
- The proportion of individuals receiving genetic risk information who subsequently visit healthcare institutions
- The number of cases in which medical visits lead to early detection or appropriate preventive interventions
- Whether providing disease risk information results in lifestyle changes
- The number of research findings translated into practical diagnosis, treatment, or prevention methods
ToMMo has already demonstrated some outcomes, such as medical consultations following the return of genetic findings.
Further evaluation of the long-term effects of these interventions and their health economic value will also be important.
5.5 Challenge 5: Sustainable Funding and Long-Term Operations
A biobank is not an infrastructure that can simply be built once and left unchanged.
Its continued operation requires substantial ongoing investment.
Examples include:
- Long-term participant follow-up
- Storage of biological samples
- Sample quality control
- Updating research datasets
- Maintenance of analysis facilities
- Information security
- Retention of specialized personnel
AMED's FY2025 evaluation emphasized the importance of sustainable operations, including funding from collaborative research with domestic and international companies in addition to public funds.
It also called for greater clarity regarding how funding is used and what outcomes it produces.[3]
Tohoku University's 2026 materials identified several operational strategies, including:
- More efficient use of limited sample storage space
- Establishment of industry consortia to support analysis costs
- Quality management based on international standards
A fundamental challenge is how to preserve academic fairness and participants' trust while maintaining a publicly supported research infrastructure and expanding collaboration with private companies.
5.6 Challenge 6: Ethical Considerations and Privacy in Returning Genetic Information
Genomic data contain information not only about an individual but also about their biological relatives.
This is particularly important in a three-generation cohort, where genetic relationships among family members are central to the research design.
For example, even when a clinically significant genetic variant is identified, an individual may not wish to receive that information.
The medical interpretation of genetic variants may also change over time, and communicating results can require specialized support.
Important considerations therefore include:
- Informed consent from research participants
- Genetic counseling
- Secure data access
- Long-term privacy protection
- Age-appropriate consent and decision-making as child participants grow older
These points do not imply that specific ethical or privacy failures have occurred at ToMMo.
Rather, they are ongoing ethical and technical considerations inherent in operating a large-scale genomic research infrastructure that includes multigenerational family information.
5.7 Summary of Challenges and Evaluation Indicators
The following table summarizes the major challenges, the situation as of 2026, and potential indicators for evaluating future progress.
| Challenge | Situation in 2026 | Important future evaluation indicators |
|---|---|---|
| Follow-up participation | Declining participation in some areas; follow-up methods being revised | Follow-up and response rates by age group and region |
| Medical record linkage | Expanding linkage with medical institutions and public records | Linkage coverage and completeness of disease outcome information |
| External data utilization | Expanding available datasets and research access support | Number of actual research uses and time required to begin using data |
| Societal implementation | Demonstrated progress in returning genetic findings | Medical consultations, preventive interventions, and clinical outcomes |
| Funding and operations | Promoting industry collaboration and operational efficiency | Sustainable funding and operating costs |
| Ethics and trust | Continued need for consent management and information protection | Participant satisfaction, consent management, and appropriate governance |
Sources: AMED evaluations and ToMMo's Phase 4 plans.[2][3]
The indicators in the right-hand column are proposed analytical measures, rather than a unified set of officially published KPIs.
6. What Does Phase 4, Beginning in FY2026, Aim to Achieve?
On August 19, 2026, Tohoku University presented the direction of ToMMo's fourth phase at a MEXT working group meeting.[2]
Four areas are particularly noteworthy.
6.1 Annual Health Surveys of Adolescents
Children who have been followed from birth through the three-generation cohort are now entering adolescence.
This makes it increasingly important to investigate changes in health status during this stage of life.
Priority research areas include:
- Hormones
- Immune function
- Allergies
- Psychological development
- Living environments
This approach goes beyond studying diseases that appear in adulthood.
It seeks to understand the processes through which health and disease risks develop over the life course.
6.2 Strengthening Research on Women's Health and Sex-Specific Medicine
The project plans to strengthen research on women's health by using longitudinal data covering adolescence, pregnancy and childbirth, menopause, and older age.
Research topics include:
- Menstrual-related conditions
- Pregnancy complications
- Menopausal symptoms
Combining longitudinal health information with genomic and multi-omics data is expected to support disease prevention and health management tailored to different stages of women's lives.
6.3 Developing a Recontact Framework for New Research
Recontact refers to a mechanism for inviting existing cohort participants to participate in additional studies, based on particular genetic characteristics or health conditions and subject to their consent.
This allows researchers not only to analyze previously collected data but also to conduct new investigations involving selected participants.
It is an important mechanism for connecting established longitudinal cohorts with emerging scientific questions.
6.4 Expanding Data Integration and Industry Collaboration
Phase 4 also emphasizes wider utilization of research data and the sustainable operation of the research infrastructure.
Major priorities include:
- Linking research data with medical records
- Conducting additional analyses, including proteomics
- Improving data access and research environments
- Securing analysis funding through industry consortia
Together, these efforts suggest that ToMMo aims to become more than a facility that stores large amounts of genomic data.
It seeks to function as a research platform that enables academic and industry researchers to conduct new studies on an ongoing basis.
However, these initiatives represent directions announced as of August 2026. They should not all be interpreted as measures that have already been fully implemented or completed.
In addition, some discussions concerning Phase 4 at the August 2026 MEXT meeting were held in closed sessions.
Consequently, certain details concerning final operational arrangements and funding allocations cannot be established from publicly available materials alone.
7. ToMMo's Position and Future Potential
Based on this review, three perspectives are particularly important when assessing ToMMo's significance and future development.
7.1 From Disaster Recovery Initiative to National Genomic Research Infrastructure
ToMMo emerged from the social need to restore healthcare following the Great East Japan Earthquake.
Since then, it has established a cohort of approximately 150,000 participants and completed whole-genome analysis for approximately 120,000 individuals.
These achievements demonstrate the substantial scale of the research infrastructure.[2]
The development of data distribution and collaborative research mechanisms has also allowed the infrastructure to serve researchers and companies beyond Tohoku University and Iwate Medical University.
As a result, ToMMo has evolved into a publicly supported research resource of national importance.
7.2 Unique Scientific Value from Family Information and Japanese Genomic Data
ToMMo's value is not determined solely by participant numbers.
Its ability to combine three-generation family information, detailed longitudinal health examinations, and genomic information from Japanese populations is particularly important.
Rather than simply replicating UK Biobank studies on a smaller scale, ToMMo has the potential to provide complementary value in areas such as:
- Adolescent health
- Women's health
- Genetic and environmental interactions within families
- Health and disease development across the life course
In these areas, ToMMo's underlying study design is itself an important scientific strength.
7.3 Moving from Data Accumulation to Real-World Implementation
The future value of ToMMo will increasingly depend on translating its research resources into meaningful outcomes for society.
Expanding data use among researchers and companies is important.
However, it is equally important to evaluate whether returning health information to participants leads to changes in health behavior or contributes to disease prevention.
The project will need to demonstrate, quantitatively, whether research findings contribute to:
- Health-related behavior changes
- Early disease detection
- Diagnosis
- Treatment
- Prevention
This direction is consistent with the priorities identified in AMED's external evaluations.[3]
7.4 Indicators Worth Monitoring in Comparison with UK Biobank
When comparing ToMMo with UK Biobank over time, five indicators are particularly useful.
- External research utilization: How extensively are the datasets used by external academic researchers and companies?
- Medical record linkage: To what extent are participants' cohort data linked with disease and clinical information?
- Long-term follow-up retention: How effectively can the project continue monitoring participants' health over extended periods?
- Clinical applications: To what extent do genomic data and research findings contribute to actual healthcare and disease prevention?
- Financial sustainability: Can the research infrastructure be maintained over the long term through public funding and industry partnerships?
These indicators can help assess how effectively ToMMo converts the achievements of building a large-scale research resource into sustained scientific and societal value.
8. Conclusion: From Building a Research Infrastructure to Utilizing It for Society
The Tohoku Medical Megabank Project (ToMMo) was conceived in response to the need for medical recovery following the Great East Japan Earthquake of 2011.
It subsequently developed into a public research infrastructure supporting genomic medicine in Japan by establishing a cohort of approximately 150,000 participants and accumulating large-scale genomic and multi-omics information.
Its distinctive characteristics—including three-generation family information, genomic characteristics of Japanese populations, detailed health examinations, and the return of information to research participants—give it scientific value that differs from that of UK Biobank.
At the same time, as the construction of its research infrastructure has progressed, new challenges have become increasingly important.
These include maintaining long-term cohort participation, expanding medical record linkage, improving data access for researchers and companies, demonstrating measurable benefits from research, and securing sustainable funding.
Phase 4, which began in FY2026, places greater emphasis on adolescent health, women's health, recontact-based research, medical record integration, and collaboration with industry.
ToMMo has made substantial progress in building its research infrastructure. It is now entering a new stage focused on making full use of the resources it has accumulated.
The central challenge going forward is whether ToMMo can maintain the quality of long-term follow-up, improve access to its research resources, and quantitatively demonstrate meaningful contributions to personalized prevention and healthcare.
Born from a major national disaster, ToMMo has the potential to continue supporting medical research in Japan while delivering tangible benefits to society.
Its evolution from disaster recovery to genomic medicine, and ultimately to real-world health applications, will remain an important development to follow.
References
[1] Tohoku Medical Megabank Organization, Tohoku University, "Background and History" (original Japanese title: 「背景と経緯」), ToMMo Official Website. https://www.megabank.tohoku.ac.jp/tommo/background
[2] Tohoku Medical Megabank Organization, Tohoku University, "Future Directions of the TMM Project" (original Japanese title: 「TMM計画の今後の方向性」), Ministry of Education, Culture, Sports, Science and Technology (MEXT), Working Group Materials, August 19, 2026. https://www.mext.go.jp/content/20260819-mext_life-000051664_03.pdf
[3] Japan Agency for Medical Research and Development (AMED), "FY2025 Post-Project Evaluation Results" (original Japanese title: 「2025年度事後評価結果」), Tohoku Medical Megabank Project-Related Programs, FY2025. https://www.amed.go.jp/program/list/14/01/008_jigo_hyoka-R07.html
[4] Tohoku University, "Announcement on the Distribution of Whole-Genome Analysis Data for Approximately 69,000 Individuals," Tohoku University Press Release, April 2026. https://www.tohoku.ac.jp/japanese/2026/04/press20260424-02-genome.html
[5] UK Biobank, "About Our Data," UK Biobank Official Website. https://www.ukbiobank.ac.uk/about-our-data/
Editor's note: This article is based on publicly available information as of November 4, 2026. Figures such as participant numbers, completed genomic analyses, and approved data distribution projects may vary depending on the reporting date. English titles of Japanese-language references are descriptive translations for readers' convenience.