Overview

a) Deletion quantitation - second tier test

This is a second-tier test to accurately quantitate the heteroplasmy levels of previously identified mtDNA deletions in samples where there is a concern regarding whether the amount of deleted mtDNA is likely to be sufficiently high to cause symptoms.

Please contact the laboratory to discuss the sample requirements and pricing for this test prior to request.

b) Depletion quantitation

Mitochondrial DNA depletion testing uses quantitative PCR to determine the amount of mtDNA in a tissue sample relative to the amount of nuclear DNA. mtDNA depletion causes a range of conditions, most often affecting liver (in hepatic presentations) or muscle (in myopathic presentations), and the testing typically needs to be performed on the affected tissue.

Category

Cost

Contact lab for price

Reporting time

Contact lab for reporting time

Contacts

P: 1300 11 8247
E: [email protected]

Specimen Requirements

Deletion: Contact lab for sample type

Depletion:

Sample Type Sample Volume
Liver (hepatic) 1-5mg
Muscle (myopathic) 1-5mg

Important notes for specimen storage and handing:

  1. Tissue biopsy/autopsy samples: Must be stored at -70°C (-20°C is inadequate) until transport on dry ice. Once frozen, they must not be allowed to thaw.
  • Postmortem Samples: COLLECT AS SOON AFTER DEATH AS POSSIBLE, preferably within 2 hours. Note the time between death and freezing of samples.
  • Liver and muscle tissue samples should be no larger than 1.0 cm cubes; heart, kidney & brain samples may also be collected.
  • Enzymes can be assayed in postmortem heart but endomyocardial microbiopsies are too small.

Notes

Please provide the following clinical details (if available) to enable optimal interpretation:

  • Patient name, medical record no., date of birth, date of sample, delay between death and freezing if relevant.
  • Full clinical summary and family history with pedigree.
  • Include copies of relevant investigations
    • urine organic & amino acids
    • tissue histology (including electron microscopy & enzyme histochemistry)
    • summary of CT, MRI or MRS studies of brain.
  • Paired plasma lactate & pyruvate levels; multiple estimations preferred.
  • Paired CSF lactate & pyruvate levels, preferably with blood levels obtained at about the same time.