- Patient Preparation
- Lavender (EDTA), 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: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics of MUTYH-Associated Polyposis (MAP): Development of colonic polyps (10-100) with the age of diagnosis occurring in the third decade or older.
Incidence: Less than 1 percent of colorectal cancer cases.
Inheritance: Autosomal recessive.
Penetrance: Greater than 99 percent in untreated individuals.
Cause: Pathogenic biallelic MUTYH gene mutations.
Clinical Sensitivity: 85 percent of MUTYH mutations in Caucasians.
Methodology: Targeted testing for the MUTYH gene mutations c.494A>G (Y165C) and c.1145G>A (G382D) by PCR and bidirectional sequencing.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Mutations in the MUTYH gene, other than Y165C and G382D, are not evaluated.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|2004912||MUTYH-Associated Polyposis Specimen||31208-2|
|2004913||MUTYH-Associated Polyposis 2 Mut Interp||40959-9|
- Familial Adenomatous Polyposis
- MAP mutation assay
- MYH-Associated Polyposis 2 Mutations