Frozen versus Fresh: What type of Muscle Sample Works Best for the Diagnosis of Mitochondrial Disease in a Clinical Laboratory?

Grant and Project Information

Date: April 2014

Award: $32,500 for one year.

Frozen versus Fresh: What type of Muscle Sample Works Best for the Diagnosis of Mitochondrial Disease in a Clinical Laboratory?

Lauren MacNeil PhD( 1), Murray Potter MD (1,3), Mark Tarnopolsky, MD, PhD(2,4)

  1. Department of Pathology and Molecular Medicine, McMaster University
  2. Departments of Pediatrics & Medicine, McMaster University
  3. Biochemical genetics laboratory, Department of Laboratory Medicine, Hamilton Health Sciences
  4. Department of Neuromuscular and Neurometabolic Diseases, Hamilton Health Sciences

Diagnosis of mitochondrial disorder is achieved using biochemical testing of a muscle biopsy. Measurement of mitochondrial function is most accurate when it is done on fresh samples shortly after collection. However, many samples are collected in locations far from a diagnostic centre and must be frozen for storage/shipping. Freezing limits the types of analyses that can be done and can introduce factors that may alter the testing results and affect the ability to correctly detect mitochondrial dysfunction. Using muscle samples collected from adult participants with and without mitochondrial disease, we will compare high resolution respirometry and enzyme activity in fresh tissue to protein and enzyme activity in frozen tissue to determine if either method is superior.