TESS Research Foundation

Cycle 1

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https://www.tessresearch.org

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SLC13A5 Epilepsy, also known as SLC13A5 Deficiency or Citrate Transporter Disorder, is a newly discovered genetic cause of epilepsy. Most people with SLC13A5 epilepsy experience seizures, movement disorders, and developmental delay.

Last updated 04/30/2026

Clinical

Disease Class

Epilepsy and seizure disorders

Genetic diseases

Inherited metabolic disorder

Intellectual disability and developmental syndromes

Neurological diseases

Body Systems

Metabolic

Muscular / Skeletal

Nervous / Sensory

Organs

Bones

Brain

Ductus deferens

Fallopian tubes

Kidneys

Liver

Mouth / teeth

Muscles

Ovaries

Penis

Prostate gland

Scrotum

Testes

Uterus

Known Genetic Link

Yes, one or more genes directly cause the condition

Causative Genes

SLC13A5

Contributory Genes

None specified / unknown

Type of Inheritance

Autosomal recessive

Newborn Screening

Disease Mechanism(s)

Citrate transporter disorder

Age of Onset

Infancy (age 0-1)

Average Age at Diagnosis

Adolescence (12-17)

Adulthood (age 18-64)

Early childhood (age 1+-5)

Infancy (age 0-1)

Middle childhood (6-11)

Pre-Birth

Life Expectancy

Adolescence (12-17)

Adulthood (age 18-64)

Early childhood (age 1+-5)

Infancy (age 0-1)

Middle childhood (6-11)

Affected Sex(es)

Female

Male

National Prevalence

11-50

Global Prevalence

101-1000

National Incidence

Less than 10

Global Incidence

Less than 10

Populations and/or ancestry with higher prevalence

Middle East, Iceland

Symptoms / Phenotypes

balance problems

developmental delay

feeding difficulties

hypodontia

intellectual delay / global developmental delay

movement disorders / ataxia / tremor

muscle weakness

seizures / epilepsy

sleep disorders

spasticity

speech delay

Biomarkers

Diagnostic

· genetic testing, elevated citrate in plasma or CSF, tooth abnormalities (minimal enamel), seizures beginning in hours/days after birth, movement disorder (ataxia)

Monitoring

· neurological/physical exam, movement disorder exam/recording, sleep disturbance scale, seizure and medication log, laboratory studies (citrate levels), neuropsychological testing (Mullen, Vineland, Peabody), EEG, Global impression of change, vital signs/growth parameters, Caregiver and quality of life reports

Prognostic

· Seizure burden/EEG, MRI, development

Therapeutic

Existing Therapies

Complementary and Alternative treatments

· physical therapy, hippotherapy, music therapy, occupational therapy, speech therapy, augmentative communication

Off-Label Drug Use

Regulatory Agency-Approved for Symptom Relief

· antiseizure medications, behavior medications (eg atypical antipsychotics), movement disorder medications (for dystonia)

Therapies in Development

Dietary & metabolic therapies (medical food, dietary restriction, supplements, etc.)

· citrulline malate

Gene therapy

· 2, TSHA-105 (clinical trials), next gen gene therapy under development

Repurposed drug

· 1, protein folding drug

Small molecule therapy (novel small molecule drugs)

· 1, rationale drug design

Therapeutic Development Stages

In clinical trials (Phase I, II, III, or IV)

Therapeutic Development Role

Access to registry or natural history study

Data analysis

Data sharing

Focus group participation or coordination

Funding

Meetings with regulators (e.g., FDA listening sessions, PFDD meetings)

Outcome measures development

Recruitment and outreach to patients

Recruitment and outreach to trial sites / physicians

Results dissemination (including publications)

Sample provision

Study material design and/or review (not protocol) — includes patient-facing materials such as informed consent

Study protocol design and/or review (includes selection of outcome measures)

Travel coordination

Organizational & Research

Cell Lines

Fibroblasts

iPSCs

NPCs

Cell Lines, Institution

Baylor College of Medicine

Neurolentech

University of North Carolina (UNC)

Cell Lines, Involvement

Consulted

Funded

Own

Cell Lines, share

Some of our cell lines are freely available

Disease Model

Drosophila/fly

Mouse

Zebrafish

Disease Model, Involvement

Consulted

Funded

Own

Disease Model, share

Some of our disease models are freely available

Organizational Challenges

money: drug development and clinical trials are incredibly expensive.

Clinical Trial Role

Data analysis

Data sharing

Focus group

Funding

Meeting with regulators

Other

Outcome measures, development

Recruitment and outreach, patients

Recruitment and outreach, trial sites/physicians

Results dissemination, publication

Study material design, review (not protocol)

Study protocol design, review

Travel coordination

Clinical Trial Types

Phase 1

Phase 2

Biobank, Institution

Baylor College of Medicine

CCR Fertility

Coriell Institute

Stanford University

University of North Carolina (UNC)

University of Texas Southwestern Medical Center (UTSW)

Biobank, Involvement

Consulted

Funded

Own

Center of Excellence, Institution

None

Registry

Yes, we have a registry that we created

Data Collected, Registry

Genetic data

Patient contact info

Data Entered by, Registry

Patients

Platform, Registry

REDCap

Natural History Study

Yes, we have a natural history study that we created

Data Collected, Natural History Study

Clinical endpoints (outcomes)

Electronic health records/electronic medical records

Genetic data

Imaging data

Medication usage

Patient-reported outcomes

Prospective data

Retrospective data

Platform, Natural History Study

REDCap

FDA Patient Listening Session

FDA Patient-Focused Drug Development (PFDD) Program

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

None