Biopolymers and cell. 1989. Volume 5. № 4. 24 - 30

G. M. Suboch, Yu. A. Sprizhitsky, A. A. Alexandrov

OCCURRENCE OF HOMOPURINE-HOMOPYRIMIDINE MIRROR REPEATS IN NATURAL DNAs

Summary

    Occurrence of the potential sites of the H-form (H-palindromes) formation in different functional regions of natural DNAs has been statistically analyzed in detail. Statistical significance of the results is estimated using model sequences and the Monte-Cario method. It is shown that the unique frequencies of H-palindromes in all the samples, with the exception of the vertebrate introns, can be explained by the effect of the nonrandom distribution of the nucleotide runs in natural DNAs. The values of frequencies of the H-palindromes occurrence are compared with frequencies of occurrence of all the homo-purine and homopyrimidine mirror repeats with length of not less than 4 bp. and at a distance from 3 to 12 bp. It is shown that sites of picks' localization in distributions for H-palindromes and purine repeats do not correlate between themselves.