Each gene was transcribed to mRNA, and subjected to translate to a protein on the ribosome (polyribosome) according to the DNA sequence of each coding region. In other words, the biological information of DNA (base sequence), when it would be the base sequence of a coding region on genome, should be transferred to a protein via mRNA (base sequence). That is, the information of the base sequence of DNA was transformed to the amino acid sequence by tRNAs corresponding to the base sequences of the mRNA on the ribosome. The coding regions varied in individual genomes and species. The non-coding sequences might be necessary for the coding regions (genes) to be expressed "when", "where" and "how" so as to be occurred in cells. In other words, the genome might be a "field" on which the four bases were sophisticatedly arranged into genes that were regulated and expressed to carry out the biological phenomena of life. Therefore, both the coding- and the noncoding-regions were arranged to form the biological information on the genome for the cells to live. The analytical methods to characterize genome structure, the SSM were needed to understand the encoded biological phenomena.
