A mutation search involves reading large parts of the gene, whereas a predictive or direct gene test is an analysis for a known mutation in a family. BOADICEA distinguishes between these two types of genetic test on the basis of their sensitivity. In particular, CanRisk assumes by default that mutation searches only detect 90% of BRCA1 mutations and 90% of BRCA2 mutations, whereas direct gene tests are assumed to be 100% sensitive. As a result, the model allows for the possibility that a mutation has been missed by a mutation search. The current BRCA1/BRCA2 mutation search sensitivities were based on UK data available when the BOADICEA model was originally developed.
The CanRisk tool includes model parameters in the 'Advanced Options' menu in the 'Family History' section that enables you to specify different BRCA mutation search sensitivities prior to running a risk calculation.
