 The development of such tools has been driven by the large amount of <unk> and <unk> data available for a variety of organisms , including the human genome . It is simply impossible to study all proteins experimentally , hence only a few are subjected to laboratory experiments while computational tools are used to <unk> to similar proteins . Such <unk> proteins can be efficiently identified in distantly related organisms by sequence alignment . <unk> and gene sequences can be searched by a variety of tools for certain properties . <unk> <unk> tools can find restriction enzyme sites , open reading frames in nucleotide sequences , and predict secondary structures . <unk> trees can be constructed and evolutionary hypotheses developed using special software like <unk> regarding the ancestry of modern organisms and the genes they express . The field of <unk> is now indispensable for the analysis of genes and proteins . 
