How does TreeFam transfer functional annotation in its gene tree displays?

In our gene tree display (e.g. http://www.treefam.org/family/TF105041#tabview=tab1), we transfer functions from SwissProt entries to all its orthologs.

Transfer of functional annotation of genes between species is routinely done using orthologs.
The validity of this method is given by the "orthology–function conjecture":
Orthologs carry our biologically equivalent, functions in different organisms, whereas paralogs typically diverge after duplication (1,2).

References:

  1. Gabaldón T, Koonin EV (2013) Functional and evolutionary implications of gene orthology. NATURE REVIEWS| GENETICS 14: 360–366. doi:10.1038/nrg3456.
  2. Koonin EV (2005) Orthologs, paralogs, and evolutionary genomics. Annu Rev Genet 39: 309–338. doi:10.1146/annurev.genet.39.073003.114725.