Microsatellite Instability (MSI)

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MSI is a change in length of a microsatellite allele due to insertion or deletion of repeating units during DNA replication and failure of the DNA mismatch repair system to correct these errors.  Samples with instability in two or more markers are defined as MSI-High (MSI-H) whereas those with one unstable marker are designated as MSI-Low (MSI-L). Samples with no detectable alterations are MSI-stable (MSS).

We accept biopsies or resection samples from patients with a possible diagnosis of Lynch syndrome.  MSI testing is also available in the context of contributing to decision-making regarding chemotherapy administration.

Please refer to the National Genomic Test Directory for Cancer here.

Reporting times

MSI 21 calendar days

Requesting a test

Please refer to our Sample Requirements section before sending any samples to us for testing.

Please use this form to request this test from us.