Detect germline PMS2 variants. Use in MMR-deficient carcinoma with suggestive IHC results (isolated loss of PMS2 protein).
- Patient Preparation
- Lavender (K2EDTA), Pink (K2EDTA), or Yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 1 week; Refrigerated: 1 month; Frozen: 6 months
Characteristics of Lynch Syndrome: Increased risk of colorectal and extra-colonic cancers including endometrial, renal pelvis, ureter, ovary, stomach, small intestine and hepatobiliary tract.
Incidence: 1-2 percent of colorectal cancer is due to mismatch repair gene mutations.
Inheritance: Autosomal dominant.
Penetrance: Unknown for PMS2 mutations.
Cause: Pathogenic germline MLH1, MSH2, MSH6, and PMS2 gene mutations.
Gene tested: PMS2
Clinical Sensitivity: Less than 5 percent of Lynch syndrome cases are due to PMS2 mutations.
Methodology: Bidirectional sequencing of PMS2 coding regions and intron-exon boundaries; multiplex ligation-dependent probe amplification (MLPA) to detect large PMS2 exonic deletions.
Analytical Sensitivity & Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations and deep intronic mutations will not be detected. Mutations in genes other than PMS2 are not evaluated. This assay is not designed to detect somatic variants associated with malignancy. Interpretation of this test result may be impacted if the patient has had an allogeneic stem cell transplantation.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|0051738||Lynch Syndrome (PMS2) Interpretation|
|2001372||PMS2 FGA Specimen|
- PMS2 gene testing
- PMS2 genotyping
- PMS2 germline assay