Eligibility and participation

Who's eligible to participate in the Mitochondrial Disease Biobank?

Participants may be males or females under 100 years of age, of any race or ethnicity and meet the criteria discussed below.

Those with a diagnosed mitochondrial disease

Those who have been diagnosed with one of the following mitochondrial diseases are eligible to participate in the biobank:

  • Alpers' progressive sclerosing poliodystrophy (Alpers' disease)
  • Leber optic neuropathy
  • Barth syndrome
  • Leigh and Leigh-like syndrome
  • Chronic progressive external ophthalmoplegia (CPEO)
  • Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS)
  • Dominant optic atrophy
  • Myoclonic epilepsy with ragged red fibers (MERRF)
  • Friedreich's ataxia
  • Neuropathy, ataxia, and retinitis pigmentosa (NARP)
  • Hereditary paraganglioma
  • Pearson syndrome
  • Hereditary spastic paraplegia
  • Wolfram syndrome
  • Kearns-Sayre syndrome

Participants may also be a first-degree relative ( a parent, sibling or child) of a potential participant with a diagnosis or suspected diagnosis of a mitochondrial disease.

Those with a suspected mitochondrial disease

Those with a suspected — but not confirmed — mitochondrial disease can participate if they meet certain criteria.

A suspected diagnosis of a mitochondrial disease is based on a review of clinical history by a Mitochondrial Disease Biobank working group member using the clinical criteria listed in the table below.

  • Selected participants shall have at least two documented conditions contained within the minor clinical criteria in the table below.
  • People with one condition in the major criteria, who also have evidence of a condition in the minor criteria, also will be considered for inclusion.
  Major Criteria Minor Criteria


  1. Multisystemic symptoms characteristic of mitochondrial disorder
  2. Progressive clinical course with episodes of exacerbation
  3. A family history strongly indicative of an mtDNA mutation
  4. Exclusion of other metabolic or nonmetabolic disorders
Symptoms compatible with a mitochondrial defect


> 2% ragged red fibers (RRFs) in skeletal muscle Smaller numbers of RRFs or widespread electron microscopy abnormalities of mitochondria


Cytochrome c oxidase negative fibers (> 2-5%) or residual activity of a mitochondrial complex < 20% in a tissue, < 30% in a cell line or < 30% in > 2 tissues Antibody-based demonstration of a mitochondrial defect or residual activity of a mitochondrial complex 20%-30% in a tissue, 30%-40% in a cell line or 30%-40% in > 2 tissues


Fibroblast ATP synthesis rates > 3 SD below mean Fibroblast ATP synthesis rates 2-3 SD below mean, or fibroblasts unable to grow in galactose media


Nuclear or mtDNA mutation of undisputed pathogenicity Nuclear or mtDNA mutation of probable pathogenicity


  One or more metabolic indicators of impaired metabolic function

Exclusion criteria

Individuals ineligible to participate in the biobank include those who:

  • Are unable or unwilling to provide informed consent
  • Are unwilling to consent to providing biospecimens to be stored in the biobank for an indefinite amount of time and to be used in future research studies of as yet unknown design
  • Do not have a diagnosis of a mitochondrial disease or clinical symptoms indicating a potential mitochondrial disease as determined by a chart review by a Mitochondrial Disease Biobank working-group member

For answers to common questions about biobank participation, please visit the Commonly Asked Questions page.