Reading between the genes

Mysterious sequences occupy 97% of the human genome which comprises vast lengths of repetitive DNA connecting the genes and numerous intron sequences that punctuate the coding regions of the genes. A comparison of DNA sequences of different species reveals limited contiguous genomic DNA sequence and the genes show a high degree of conservation of the order of 75%. A survey of the entire region including 94% non-coding DNA produces a 71% similarity between mice and humans. The degree of sequence conservation is due to chromosomes which serve as 'information organelles' for storage, copying and evolution of information.