Specimen Requirements

Selecting the Appropriate Sample Type

Please contact us if you would like assistance with choosing a sample type for a specific case.

Mitochondrial DNA tests: Muscle and other post-mitotic tissues confer a higher detection rate for mitochondrial DNA mutations than blood samples. Muscle or tissue samples are, therefore, strongly preferred for the majority of mitochondrial DNA assays.

MELAS (A3243G tRNA Lys1): If muscle is not available, urine sediment has been shown to give the next highest heteroplasmy level for the 3243 mutation. Shanske et al. Am Journ Med Gen. 2004; 130:134-7. Urine heteroplasmy level has also recently been shown to be a better clinical predictor of clinical outcome than muscle heteroplasmy for the 3243 mutation. Whittaker et al. Neurology. 2009 Feb 10;72(6):568-9. Testing of a urine sample is strongly recommended for 3243 testing.

Specimen Collection, Handling and Transport

Blood Samples

For DNA Analysis: Blood specimens for DNA testing must be drawn in a lavender top (EDTA) tube. Blood samples should be sent to Mitomed by overnight courier at room temperature as soon as possible after being drawn. If the specimen can not be sent immediately, it should be stored refrigerated at 4 degrees C. The blood specimen must not be stored for more than 3 days at 4 degrees C.
- Adults: 6-9 cc
- Children: 1-3 cc

Tissue samples

Tissue Samples must be flash frozen, and shipped on dry ice by overnight courier. Please call the laboratory prior to sending any tissue sample.
* DNA Analysis: Samples that have been treated with isopentane are acceptable.

Urine Samples for A3243G MELAS testing

Please send 30-50 mL of urine in a tightly sealed and parafilmed container at 4 degrees C or room temperature by overnight courier. First morning urine is preferred as it yields the highest amount of DNA. It is not necessary to perform a clean catch collection; the first portion of the stream will yield more cells.