Real and complex genomic signals

The paper discusses the ways of converting DNA sequences from their symbolic - nucleotide, codon and amino acid - forms into corresponding digital signals. It is shown that all the real and complex mappings can be derived from the same original tetrahedral representation of the genetic code (GC). The reduction of the representation dimensionality results from the projection of the GC tetrahedron on adequately oriented planes or surfaces. On these bases, optimal symbolic-to-digital mappings of the DNA strands into real or complex genomic signals are derived at nucleotide, codon and amino acid levels. By converting the nucleic acid and polypeptide sequences into digital genomic signals, this approach offers the possibility to use a large variety of signal processing methods for their handling and analysis. It is also shown that some essential features of the nucleotide sequences can be better extracted using this representation. Results obtained by applying this approach for the analysis of the human genome are presented along with some new methods for identifying genetically significant segments of DNA sequences.