Variants categorisation (according to: http://www.hgvs.org/entry.html):
Mutation associated with disease comprise: nonsense variants, insertions, deletions, missense variants published as pathogenic ones and splicing variants located at positions donor+1 and acceptor-1 or other splicing affecting variants, which were proved by mRNA/cDNA analysis to be pathogenic (basis on published data or personal communnication).
Polymorphism not causing disease comprise: variants with frequency equal or exceeding 1% in general population
Don't know comprise: variants without obvious deleterious effect, with unknown frequency or frequency less than 1% in general population