What Can Be Learned From This Test
Testing is performed by sequencing the entire coding region of POLR3A and POLR3B. This will detect point mutations, small deletions and small insertions. It will not detect a partial or whole gene deletion or duplication. A negative test result does not rule out a genetic cause of hypomyelinating leukodystrophy, since there are many other genes associated with leukodystrophies, some of which are available for testing in our lab.
Sequencing of POLR3A with reflex to sequencing of POLR3B is recommended, however, testing can be done concurrently or in any order specified.
Draw 2ml–4ml of blood in EDTA/purple-top tube (minimum of 1ml–2ml for infants).
Turnaround time: 10-14 business days per gene
CPT Codes and Cost
Full Gene Sequencing
Known Variant Testing