Biological sequences can be broadly categorized into two types: sequences of nucleic acids (DNA and RNA) identified by the coding letters A, U or T, C, and G, which identify nucleotides with particular base-pairing relationships; and polypeptide, peptide or protein sequences (linear polymers of amino acids either identified by a single letter alphabetic code or a three letter code, e.g. "S" or "Ser" for the amino acid serine)...
The challenge in claim construction is that biological function is usually not dependent on the exact sequence, and similar or homologous functions can be “encoded” by many variations that might be only weakly similar to the particular sequences in the specification. Thus, claims are seldom over a single exact sequence, and tend to be worded such that they read on many sequences that may be found in the literature.
Different types of sequence searches can be conducted:
> Exact, where results exactly match the sequence searched
> Subsequence, where results include the sequence searched and sequences that include additional amino acid or nucleic acid segments
> Homology, where computer algorithms score sequences based on their similarity to the sequence searched