Mosaic organization of DNA nucleotides

TLDR

DNA sequences with noncoding regions exhibit long‑range power‑law correlations. The study investigates whether these correlations arise simply from DNA’s mosaic patchiness. The authors compare two algorithmically generated patchy nucleotide sequences, one lacking and one containing long‑range correlations. A novel fluctuation‑analysis method distinguishes patchiness from long‑range correlations, showing that patchiness alone cannot explain the observed long‑range correlation properties in DNA.

Abstract

Long-range power-law correlations have been reported recently for DNA sequences containing noncoding regions. We address the question of whether such correlations may be a trivial consequence of the known mosaic structure (``patchiness'') of DNA. We analyze two classes of controls consisting of patchy nucleotide sequences generated by different algorithms---one without and one with long-range power-law correlations. Although both types of sequences are highly heterogeneous, they are quantitatively distinguishable by new fluctuation analysis method that differentiates local patchiness from long-range correlations. Application of this analysis to selected DNA sequences demonstrates that patchiness is not sufficient to account for long-range correlation properties.