Why are there differences in SIFT scores between Alamut Visual and AlamutTM Visual Plus?

In Alamut Visual and AlamutTM Visual Plus, the SIFT missense predictors are computed using the orthologues alignment. Differences in SIFT scores can be explained by differences in orthologue alignment. Alamut Visual contains ‘in-house’ orthologues for some genes, whereas AlamutTM Visual Plus contains Ensembl orthologues.