Homology mutations in the relm of biochemistry is also used for determining the importance of an amino acid from the primary sequence of a protein. For instance to determine if Tyr1163 is important for phosphorylation of receptor tyrosine kinases they may substitute a homologous amino acid such as Phe which has relativly the same size as the Try but missing the hydroxyl group. Thus is catalytic acitivity is maintained with the mutation then it can be stated that they Tyr residue has little or no important to the catalytic efficience of this enzyme. (Hubbard, et al. 1997) Other homologous mutations would be from Gly to Ala Phe-Ala, etc.
I'm not sure the list of external links is that relevant to the article. I know of a few labs that do Homology modelling and belong to these institutions, but it's a bit too generic. I'm not a big fan of lists of things put together, maybe links to homology modelling servers would be more appropriate. Blastwizard (talk) 18:51, 19 March 2008 (UTC)