Risk Assessment; Diagnosis; Pre-symptomatic; Mutation Confirmation

Guidance for management

Families with a history of polyposis or hereditary colorectal cancer

Previousy registered in GTR as GTR000172265; COLARIS AP Plus testing includes sequencing and deletion/duplication testing of both APC and MUTYH.

Tests performed
Entire test performed in-house

Analytical specificity: The incidence of a false report of a genetic variant or mutation resulting from technical error is considered negligible because of independent confirmation of all clinically significant genetic variants (see below). The incidence of a false report of a clinically significant genetic variante or mutation resulting from errors … Analytical specificity: The incidence of a false report of a genetic variant or mutation resulting from technical error is considered negligible because of independent confirmation of all clinically significant genetic variants (see below). The incidence of a false report of a clinically significant genetic variante or mutation resulting from errors in specimen handling and tracking was assessed by performing a comparison of all eligible variants in 6,882 samples which underwent at least two independent DNA extractions and cycles of NGS testing. No evidence of sample switches was found during this comparison; therefore, the incidence of a false report of a clinically significant genetic variant or mutation is estimated to be <0.000033% (upper bound of the 95%CI). View more

Limitations of method: Unequal allele frequencies may result from certain DNA contexts, including repetitive or low complexity sequences. The presence of pseudogenes or gene conversion may complicate the detection of rare sequencing and copy number variation mutations in certain genes. Due to the potential location and complexity of transposon insertions, … Limitations of method: Unequal allele frequencies may result from certain DNA contexts, including repetitive or low complexity sequences. The presence of pseudogenes or gene conversion may complicate the detection of rare sequencing and copy number variation mutations in certain genes. Due to the potential location and complexity of transposon insertions, not all events may be detected. There may be uncommon genetic abnormalities such as specific insertions, inversions and certain regulatory mutations that will not be detected by myRisk. This analysis, however, is believed to rule out the majority of abnormalities in the genes analyzed. Genetic testing results on blood or buccal saliva samples may not reflect the germline genetic status of patients with a hematologic malignancy, or patients who underwent allogeneic bone marrow transplants. View more

Is proficiency testing performed for this test? Help
Yes

Method used for proficiency testing: Help
Alternative Assessment

PT Provider: Help
Internal proficiency assessment

Description of PT method: Help
Intra-Laboratory

Description of internal test validation method: Help
Blinded internal proficiency testing

Software used to interpret novel variations Help
In house developed analytical tools.

Laboratory's policy on reporting novel variations Help
All non-polymorphism variations are reported