Barth Syndrome Foundation
Cycle 3
Barth syndrome (BTHS; OMIM #302060) is a serious X-linked genetic disorder, primarily affecting males. It is caused by a mutation in the tafazzin gene (TAZ, also called G4.5), resulting in an inborn error of lipid metabolism.
Last updated 04/30/2026
Clinical
Disease Class
Cardiac diseases
Genetic diseases
Hematological diseases
Inherited metabolic disorder
Mitochondrial disease
Multi-system genetic syndromes
Muscular and neuromuscular diseases
Body Systems
Cardiovascular / Circulatory
Digestive
Endocrine
Hematopoietic / Lymphatic / Immune
Metabolic
Muscular / Skeletal
Renal / Urinary / Excretory
Organs
Bladder
Blood
Bone marrow
Bones
Connective tissue / joints
Heart
Intestines
Mouth / teeth
Muscles
Pancreas
Stomach
Known Genetic Link
Yes, one or more genes directly cause the condition
Causative Genes
TAFAZZIN
Contributory Genes
None specified / unknown
Type of Inheritance
X-linked recessive
Newborn Screening
No
Disease Mechanism(s)
Aberrant immune response
Enzyme deficiency
Immune deficiencies
Lipid metabolism disorder
Mitochondrial defects
Organic acid metabolism defect
Age of Onset
Early childhood (age 1+-5)
Infancy (age 0-1)
Prebirth
Average Age at Diagnosis
Early childhood (age 1+-5)
Infancy (age 0-1)
Life Expectancy
Adulthood (age 18-64)
Early childhood (age 1+-5)
Affected Sex(es)
Male
National Prevalence
101-1000
Global Prevalence
101-1000
National Incidence
Less than 10
Global Incidence
Less than 10
Symptoms / Phenotypes
cardiac abnormalities
failure to thrive
fatigue
gastrointestinal disorders
myopathy
neutropenia
Biomarkers
Diagnostic
· TAFAZZIN sequencing, MLCL:CL LC-MS/MS assay
Therapeutic
· MLCL:CL LC-MS/MS assay (for therapies acting directly on TAFAZZIN, e.g. Gene Replacement Therapy)
Existing Therapies
Expanded access (Compassionate Use)
Regulatory Agency-Approved for Symptom Relief
· Forzinity (Elamipretide): approved 9/19/2025
Therapies in Development
Antisense oligonucleotide (ASO) therapy
Dietary & metabolic therapies (medical food, dietary restriction, supplements, etc.)
· Nicotinamide Riboside
Gene therapy
· TAFAZZIN Gene Replacement Therapy
Small molecule therapy (novel small molecule drugs)
· Forzinity (elamipretide; approved), small molecules targeting ABHD18 for inhibition
Therapeutic Development Stages
Approved/Available
In clinical trials (Phase I, II, III, or IV)
In preclinical development
Therapeutic Development Role
Access to registry or natural history study
Data sharing
Focus group participation or coordination
Meetings with regulators (e.g., FDA listening sessions, PFDD meetings)
Recruitment and outreach to patients
Recruitment and outreach to trial sites / physicians
Results dissemination (including publications)
Organizational & Research
Cell Lines
iPSCs
Lymphoblasts
Cell Lines, Institution
Boston Children's Hospital
Kennedy Kreiger
Cell Lines, Involvement
Consulted
Cell Lines, share
Some of our cell lines are freely available
Disease Model
Mouse
Disease Model, Involvement
Funded
Own
Disease Model, share
All our disease models are freely available
Organizational Challenges
None
Clinical Trial Role
Data sharing
Focus group
Meeting with regulators
Recruitment and outreach, patients
Results dissemination, publication
Study material design, review (not protocol)
Study protocol design, review
Clinical Trial Types
Observational
Phase 1
Phase 2
Phase 3
Phase 4
Biobank, Institution
Van Andel Institute
Biobank, Involvement
Own
Center of Excellence, Institution
Amsterdam University Medical Center
Johns Hopkins Hospital
Kennedy Kreiger
NHS National Barth Syndrome Service
University Hospitals Bristol and Weston
University of Mississippi
Center of Excellence, Involvement
Consulted
Funded
Registry
Yes, we have a registry that we created
Data Collected, Registry
Clinical data
Genetic data
Imaging data
Longitudinal natural history data
Medication usage
Patient contact info
Patient-reported data
Data Entered by, Registry
Patients
Platform, Registry
Matrix
Natural History Study
Yes, we have collaborated on a natural history study
Data Collected, Natural History Study
Clinical endpoints (outcomes)
Electronic health records/electronic medical records
Genetic data
Medication usage
Patient-reported outcomes
Prospective data
Retrospective data
Platform, Natural History Study
Matrix
FDA Patient Listening Session
Yes
FDA Patient-Focused Drug Development (PFDD) Program
Yes
ICD Codes
Yes, we have an ICD-10 code specific to our exact disease
Diagnostic Guidelines
Yes, we have guidance available on our website
Science Advisory Board Policies
Yes, willing to share SAB policies
Research Network Policies
Has CRN and willing to share policies
Patient Priority Survey
Yes
Patient Priority Survey, share
Yes, will share
Research Roadmap
Yes we have a Research Roadmap, and will share policies
International Chapters
Europe
North America
International Partners
None
Other International Research Initiatives
None