Finding groups of seqeunces
  Let's say that you know which related human proteins you want to contrast, and study for the evidence of specialization. Uniprot then provides a number of links to databases - wiht the varying degree of user friendliness - that tabulate orthologues across species, using your protein as the input.  
  HGNC Gene Families/Groupings Nomenclature  
  Taxonomical grouping of sequences