Region assignment (Fig 3)

Finally, based on the regions previously identified, an unsupervised classification with model selection criteria allows a status to be assigned for each region (gain, loss or normal). Our algorithm involves three steps:

1. First, for each chromosome, regions are grouped in classes, each class containing regions of the same expected (but unknown) DNA copy number.
2. Second, the resulting classes for all chromosomes are clustered to produce superclasses, of same expected DNA copy number.
3. Finally, each superclass is given a status: gain, normal or loss.

Figure 3: Status