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NASA NTRS · 20040142072

Generalized Levy-walk model for DNA nucleotide sequences

Buldyrev, S. V.·Goldberger, A. L.·Havlin, S.·Simons, M.·Stanley, H. E.
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Abstract

We propose a generalized Levy walk to model fractal landscapes observed in noncoding DNA sequences. We find that this model provides a very close approximation to the empirical data and explains a number of statistical properties of genomic DNA sequences such as the distribution of strand-biased regions (those with an excess of one type of nucleotide) as well as local changes in the slope of the correlation exponent alpha. The generalized Levy-walk model simultaneously accounts for the long-range correlations in noncoding DNA sequences and for the apparently paradoxical finding of long subregions of biased random walks (length lj) within these correlated sequences. In the generalized Levy-walk model, the lj are chosen from a power-law distribution P(lj) varies as lj(-mu). The correlation exponent alpha is related to mu through alpha = 2-mu/2 if 2 < mu < 3. The model is consistent with the finding of "repetitive elements" of variable length interspersed within noncoding DNA.

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NASA Discipline Number 14-10NASA Discipline CardiopulmonaryNon-NASA CenterModels, StatisticalDNASequence Analysis, DNA/methodsSupport, Non-U.S. Gov'tFractalsChromosome WalkingNucleotides/analysisBase SequenceSupport, U.S. Gov't, Non-P.H.SSupport, U.S. Gov't, P.H.S

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Buldyrev, S. V., Goldberger, A. L., Havlin, S., Simons, M., Stanley, H. E.. 1993-06-01. Generalized Levy-walk model for DNA nucleotide sequences. https://ntrs.nasa.gov/citations/20040142072

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