bims-curels Biomed News
on Leigh syndrome
Issue of 2025–11–02
fifteen papers selected by
Cure Mito Foundation



  1. Mitochondrion. 2025 Oct 29. pii: S1567-7249(25)00090-X. [Epub ahead of print] 102093
      The recent development of mitochondrial base editors (mitoBEs) has ushered in a transformational time that has overcome some long-standing limitations in the field of mitochondrial genetics. By closely tracing mitoBE development from the earliest tool mitochondria targeted TALENs to the most recent base editing systems that can precisely convert C•G → T•A and A•T → G•C, we review mitoBEs. We describe the development of recent advancements in mitoBEs including the generation of second generation mitoBEs (mitoBEs v2), which have evidence to identify over 70 mouse mtDNA mutations comparable to human pathogenic variants. Notably, in order to incorporate circular RNA (circRNA) as a delivery vector the editing efficiency has been increased by over 82 %, without experimental evidence of off-target effects. Taking advantage of these gains in technology, these mouse models of mitochondrial diseases, including those associated with Leigh syndrome and LHN, are highly faithful. These models have also confirmed that these specific mtDNA variants have pathological phenotypic evaluations, and have compared to previous editing strategies, mitoBEs v2 have demonstrated improved specificity, stability and safety. We finally discuss the future of mitochondrial base editing and outline the ways it will move forward towards therapeutic potentials in the treatment of the mitochondrial disorders and also in precision medicine.
    Keywords:  ABE; CBE; Mitochondrial diseases; TALED; circRNA; mitoBEs; mtDNA
    DOI:  https://doi.org/10.1016/j.mito.2025.102093
  2. J Vis Exp. 2025 Oct 10.
      Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like episodes (MELAS) are mitochondrial disorders most commonly caused by a m.3243A>G variant in mitochondrial tRNALeu. To investigate the pathophysiology of MELAS, we generated brain organoids from multiple induced pluripotent stem cell (iPSC) lines derived from a patient with MELAS carrying the m.3243A>G variant. These lines share an identical nuclear genetic background but differ in their heteroplasmy levels involving the m.3243A>G variant. We observed significant differences in organoid size, morphology, and neural induction efficiency, which correlated with the degree of heteroplasmy. Dissociated neurons from the organoids were transferred into a 2D-culture system, which is convenient and suitable for high-throughput drug screening. The organoids also exhibited significant differences in the formation of neural networks, depending on heteroplasmy levels. Our results suggest that patient-derived iPSC-based organoid models represent a useful platform for studying MELAS mechanisms and for drug screening. This video presents comprehensive and user-friendly methods, including protocols for generating organoids and evaluating phenotypes.
    DOI:  https://doi.org/10.3791/69303
  3. J Cell Sci. 2025 Oct 15. pii: jcs264320. [Epub ahead of print]138(20):
      For researchers and clinician-scientists, forging partnerships with patient-led rare disease organizations can be a challenge. Patient-led rare disease organizations often operate quite differently to research and medical institutions, large private or public funding organizations, and pharmaceutical or biotechnology companies, leaving researchers and clinician-scientists uncertain about how, when and where to engage for mutual benefit. However, the value of reciprocal engagement can be immense, paying dividends in new research directions, accelerating existing research, facilitating access to funding and achieving success in translation. Most importantly, it can improve the lives of individuals with disease. In this Perspective, we will explore the value of engaging and collaborating with patient-led rare disease organizations through the lens of a rare syndromic ciliopathy - Bardet-Biedl syndrome (BBS) - for which patient-led organizations exist in multiple countries. We explain what researchers should know about how rare disease organizations operate, discuss examples of successful engagement between researchers, clinician-scientists and patient-led organizations, and review the 'do's and don't's' of successful collaboration.
    Keywords:  Bardet–Biedl syndrome; Ciliopathies; Collaboration; Patient-led rare disease organization; Rare genetic diseases
    DOI:  https://doi.org/10.1242/jcs.264320
  4. Learn Health Syst. 2025 Oct;9(4): e70033
       Introduction: Patients, caregivers, and community partners (PCC) can have a variety of roles in learning health systems (LHS), such as contributing their data from healthcare encounters to embedded, continuous engagement where they identify health system priorities, guide operational, research, and quality improvement decisions, and facilitate knowledge sharing and implementation. Despite many LHS models placing emphasis on PCC, little has been done to help members of the public understand what a LHS is or initiate dialogue about how they can learn more and become engaged. We brought together a national network of PCC to co-create an everyday language, arts-based resource for the public to learn what a LHS is and how it relates to patient care journeys.
    Methods: Thirteen PCC with LHS experience from across Canada attended two 2-h virtual workshops to generate ideas on how to better define LHS using everyday language, determine accessible ways to share this information, and co-design a comic strip that can be widely shared across diverse settings and communities.
    Results: We co-created a six-panel comic strip that depicts a relatable patient experience of waiting in an emergency department. The comic shows that in a LHS, patients are invited to contribute their perspectives about improving healthcare and support implementing and testing new ideas in clinical settings. Creating this comic was considered important for various reasons: to promote a common language around LHS, to build trust between health systems and the public, and to widen the community of PCC who are engaged in LHS activities.
    Conclusions: This comic is intended to build capacity for LHS culture, where the public can understand how continuous learning and improvement fit within health care, and learn about opportunities for engagement in LHS.
    Keywords:  accessibility; co‐design; engagement; patient partnership
    DOI:  https://doi.org/10.1002/lrh2.70033
  5. Commun Med (Lond). 2025 Oct 31. 5(1): 449
       BACKGROUND: Rare disease clinical trials face unique challenges, resulting in low enrollment and limited retention. Digital health technologies (DHTs), when applied through a patient-centric lens, offer promising solutions to these challenges by enhancing data collection efficiency, improving patient engagement, and supporting long-term health care.
    METHODS: This study investigates DHT application in clinical studies across the ten most-studied rare diseases and was registered with PROSPERO (registration number: CRD420251088025). Up to June 26 2024, a total of 262 studies were identified through ClinicalTrials.gov, the International Clinical Trials Registry Platform, Cochrane Central Register of Controlled Trials, PubMed, and Web of Science. DHT applications were classified into patient recruitment, digital treatment, data monitoring and collection, outcome assessment, remote follow-up, and long-term care management based on scenarios and functionalities.
    RESULTS: Among all DHT applications, data monitoring and collection was the most prevalent (31.3%), serving primarily to enable continuous tracking of physiological parameters relevant to specific rare disease conditions. Digital treatment is featured in 57 studies (21.8%), most commonly as digital physiotherapy. A notable increase in DHT adoption is observed from 2017-2020 to 2021-2024 across nearly all ten diseases. Between 2021 and 2024, cystic fibrosis shows the highest proportion of DHT-enabled trials relative to all studies conducted for that disease (29.7%).
    CONCLUSIONS: Our findings reveal a growing trend toward digital integration in rare disease trials to support decentralized, scalable, and patient-centered research models. We propose a "4A" conceptual framework-Accessibility, Agility, Awareness, and Adaptability to accelerate therapeutic development and expand access to care for these underserved rare disease populations.
    DOI:  https://doi.org/10.1038/s43856-025-01137-6
  6. BMJ Open. 2025 Oct 27. 15(10): e105045
       BACKGROUND: The vast majority of healthcare research in the UK is investigator-led. While national progress in patient and public involvement (PPI) increasingly mandates patient consultation, research questions and outcomes still frequently misalign with patient priorities. This is particularly important in rare disease research, as more than 95% of 11 000 conditions have no effective or curative treatment, and around 20% are not clinically defined, making them difficult to diagnose and manage. The unmet physical, mental and emotional needs of people living with rare diseases are immense. Extensive guidance and toolkits exist to support investigators with PPI, but none target patient communities attempting to promote their own priorities, initiate or co-lead research.
    AIM: This communication article introduces the newly established patient-led Rare Disease Research Network (RDRN). WHAT IS THE RDRN, AND HOW CAN IT BE USEFUL?: Launched in November 2024, the RDRN is an open-access collaborative platform designed to support patient-driven and co-produced research, connecting patient and professional partners with similar research interests. Originally conceived by an ultra-rare patient group, the network was co-produced with the rare disease community, including individuals living with rare conditions, parents, carers and charity advocates, whose lived experience and priorities shaped every aspect of its design. Supported by academic and research networks, its collaborative development ensures RDRN removes barriers to participation while complementing existing initiatives. RDRN is a novel approach to driving new impactful research by aligning investigator priorities with real-world needs and building capacity from patients outward. Rare disease communities bring lived expertise, creativity and motivation. Yet without a structured route to collaborate, their insights are often lost. RDRN offers an inclusive space, fostering new partnerships and supporting upstream collaboration. The approach enables patients to become 'research ready' and empowers them to have an active role in generating ideas and delivering research from inception, leading to innovative research and driving meaningful change in patients' lives. With further development, RDRN could present a lasting, scalable and unified model for co-designed rare disease research. By enabling trust, capacity and shared purpose, it can drive discovery, improve outcomes and build a more resilient and self-sustaining research ecosystem, underpinning key pillars of the 2021 UK Rare Diseases Framework.
    Keywords:  Community-Based Participatory Research; Digital Technology; Health Equity; Organisational development; Patient Participation; Rare Diseases
    DOI:  https://doi.org/10.1136/bmjopen-2025-105045
  7. AJOB Empir Bioeth. 2025 Oct 28. 1-11
       BACKGROUND: A number of patient organizations have recently embraced venture philanthropy, a model of patient advocacy that purports to use practices from venture capitalism in pursuit of philanthropic goals. However, a clear understanding of what venture philanthropy entails and what these organizations do remains elusive, hindering efforts to assess ethical implications of the model's growth.
    METHODS: We conducted a qualitative content analysis of self-reported profiles of 130 organizations in an affinity network promoting principles of venture philanthropy. We analyzed organizations' research goals, funding strategies, activities, and patient engagement efforts.
    RESULTS: Despite finding substantial variation in age, revenue, and disease focus, we identified shared assumptions and approaches that represent defining characteristics of venture philanthropy. First, organizations consistently present facilitating the development of new therapies as the most urgent need for patients. Second, organizations participate in financing and managing research across the development pipeline, rather than focusing on basic research as many patient organizations historically have done. Third, organizations seek to position themselves within established research and drug development networks, fostering collaborative relationships with key stakeholders, including pharmaceutical companies. We also find that some of the most transformative practices associated with venture philanthropy, such as direct investment in for-profit companies, remain relatively uncommon.
    CONCLUSIONS: Venture philanthropy represents an evolution in the ambitions and activities of patient organizations, with organizations becoming more fully enmeshed in the drug development process. Our findings raise ethical questions about how patient organizations conceptualize and advance patient interests and about tradeoffs inherent to the venture philanthropy model.
    Keywords:  Patient advocacy; charities; consumer organizations; organizational ethics; rare disease
    DOI:  https://doi.org/10.1080/23294515.2025.2576835
  8. Orphanet J Rare Dis. 2025 Oct 27. 20(1): 543
       BACKGROUND: Persons living with a rare disease (PLWRD) often encounter burdensome and stressful events that may severely affect their psychosocial vulnerability. There is an urgent need for psychosocial support in PLWRD. We aimed to reach consensus about the most prominent psychosocial needs in rare diseases and future research directions to develop adequate psychosocial support for rare diseases.
    METHODS: An adapted nominal group technique (NGT) session was conducted in Nijmegen (The Netherlands) with a European expert group of professionals working in the rare disease field. Seventeen participants from seven different European countries took part in the NGT session (seven researchers, two therapists, one patient representative, four clinicians/researchers, and three clinicians), and 23 participants took part in the overall workshop and contributed to this consensus statement.
    RESULTS: An initial list of 57 psychosocial needs was aligned with Pickers' theoretical framework of eight principles of care: patient-centredness, emotional support, access to care, information and education, partner and family involvement, respect and autonomy, care organisation, continuity of care, and physical comfort. For future research directions, six items remained with main focal points addressing international collaborations, inclusivity in rare diseases (patient representatives, ethnic minorities, and elderly), identifying common needs across rare diseases, and translating psychosocial models from common chronic conditions.
    CONCLUSIONS: A consensus meeting was organised that primarily addressed the psychosocial vulnerability in rare diseases. With the outcomes of this study, we aim for better representation of psychosocial vulnerability within health care and to create future research directions to reduce psychosocial vulnerability in rare diseases.
    Keywords:  Consensus workshop; Psychosocial factors; Quality of life; Rare diseases
    DOI:  https://doi.org/10.1186/s13023-025-04017-3
  9. Radiol Case Rep. 2025 Dec;20(12): 5929-5933
      Spinal cord involvement in Leigh syndrome (LS) due to an NDUFV1 variant has rarely been reported. The patient is a 4-month-old girl who developed generalized weakness, decreased vigilance, lethargy, cyanosis and unresponsiveness. Investigation revealed lactic acidosis, mild hyponatremia, normocytic anemia, elevated troponin, elevated pro-brain natriuretic peptide, Mobitz II block, systolic dysfunction, and pulmonary hypertension. Cerebral MRI showed symmetrical T2 hyperintensities in the brainstem and supra-tentorial, suggestive of LS, as well as T2 and STIR hyperintensities of the fasciculus gracilis and posterior and lateral gray matter horns, which were hypointense at T1. Seventeen days later, these lesions were more pronounced on T2 and STIR than before. Genetic testing revealed the compound heterozygous variants c.1162+4A>C and c.1138G>C in NDUFV1. In summary, mutations in NDUFV1 can also manifest phenotypically in the spinal cord and present clinically with sensory disturbances, spasticity and spinal ataxia. In patients with LS due to NDUFV1 variants, not only imaging of the brain but also of the spinal cord should be performed.
    Keywords:  Complex-I deficiency; Leigh syndrome; Mitochondrial DNA; NDUFV1; Respiratory chain
    DOI:  https://doi.org/10.1016/j.radcr.2025.08.031
  10. EBioMedicine. 2025 Oct 30. pii: S2352-3964(25)00409-8. [Epub ahead of print]121 105965
       BACKGROUND: Deep phenotyping is important for rare disease diagnostics, often using the Human Phenotype Ontology (HPO). Patients are an under-utilised source; to facilitate self-phenotyping we previously "translated" HPO into plain language. However, self-reported data has not been assessed to date for diagnostic efficacy nor patient opportunities for collaboration with clinical diagnosticians.
    METHODS: Approximately one-third of the HPO is translatable to layperson HPO terms. We used two instruments to evaluate patients' use of the layperson HPO - the GenomeConnect survey mapped to layperson HPO terms, and a natively layperson HPO-based application, Phenotypr. We created phenotype profiles for 7344 Mendelian diseases for each instrument, representing the theoretical maximum performance that patients might achieve. To explore real-world capabilities, we randomised participants with diagnosed genetic diseases to use GenomeConnect, Phenotypr, or both instruments. For each diagnosed disease, we compared the layperson HPO profile to the patient-completed profile for each instrument. We also performed qualitative interviews.
    FINDINGS: Both instruments performed well in retrieving the correct disease (area under the curve 0.991 and 0.954). Profiles resulting from participant responses to the GenomeConnect survey were more accurate than Phenotypr. Phenotypr had a tighter distribution of scores for respondents who did both instruments and was more precise. We conducted interviews and generally participants preferred the GenomeConnect multiple choice format over the autocomplete Phenotypr format and valued the opportunity to contribute to their diagnostic workup.
    INTERPRETATION: Our results demonstrate that individuals are capable of providing rich phenotype data and suggest that self-phenotyping could be used to supplement profiles created by clinicians, providing a more robust foundation for rare disease patient engagement and reducing burden on clinical diagnosticians. Further user interface innovation is needed to garner maximally useful phenotype data from patients.
    FUNDING: This research was supported by PCORI #HSRP20181624. The Manton Foundation provided philanthropic support for patient studies. NIH P50HD105351 provided support for genotyping patients at BCH.
    Keywords:  Clinical genetics; Diagnostics; Ontology; Phenotyping; Rare disease
    DOI:  https://doi.org/10.1016/j.ebiom.2025.105965
  11. Curr Med Chem. 2025 Oct 24.
      
    Keywords:  Atherosclerosis; CRISPR-Cas9; cybrid; disease model; drug discovery.; epigenetic regulation; gene editing; gene regulation; mitochondrial DNA mutations; next-generation sequencing
    DOI:  https://doi.org/10.2174/0109298673450033251020095814
  12. Curr Opin Neurobiol. 2025 Oct 30. pii: S0959-4388(25)00163-1. [Epub ahead of print]95 103132
      Since their discovery and development, human induced pluripotent stem cells (iPSCs) have brought about notable advances in biomedical science and have become an essential infrastructure for medical research and applications. This review discusses the current status of iPSC-based cell therapies, drug discovery, and therapeutic developments for neurodegenerative diseases with unmet medical needs. It also highlights research approaches employing cohorts of iPSCs derived from sporadic neurodegenerative diseases to advance prevention and diagnostic support. It further considers future directions for the use of iPSCs in the treatment of neurodegenerative disorders.
    DOI:  https://doi.org/10.1016/j.conb.2025.103132
  13. Mol Genet Metab. 2025 Oct 24. pii: S1096-7192(25)00256-2. [Epub ahead of print]146(4): 109264
      
    DOI:  https://doi.org/10.1016/j.ymgme.2025.109264
  14. Clin Teach. 2025 ;22(6): e70235
       BACKGROUND: Bedside clinical teaching is a fundamental part of the medical education that offers invaluable opportunities for the students to build and improve their clinical and communication skills. However, there is a growing concern about the increasing refusal of patients to participate in clinical sessions, especially in certain settings where there are sensitive cultural traditions and decreased trust in institutions.
    AIM: This paper discusses patient refusal during bedside clinical teaching and views it from three aspects, that of the medical student, the clinical educator and the patient, and proposes culturally sensitive strategies that balance patient autonomy with educational needs.
    PERSPECTIVE: Patient refusals reduce the students' chances of hands-on learning, placing the educator under ethical strain and emotional fatigue. These refusals are not simply uncomfortable incidents, but they signal underlying systemic gaps such as lack of transparent communication with the patients, failure to adapt to the social development and deep cultural dissonance. While simulation offers partial relief, it cannot fully replace the human dimensions of real patient interactions.
    CONCLUSION: Patients' reluctance is a meaningful message that needs to be heard. A thoughtful reform including coordinated efforts at the level of patient education, faculty support, student preparation and institutional policy is needed. Without reform, we risk graduating doctors who have never truly encountered the human side of medicine.
    Keywords:  autonomy; bedside teaching; medical education; patients' refusal
    DOI:  https://doi.org/10.1111/tct.70235