[Statistics of periodic regularities in sequences of human introns]

A formula for the calculation of average power of a Fourier harmonic of a nucleotide sequence with given composition by means of the matrix Fourier analysis method is suggested. A search for the periodic regularities with the periods from two to ten nucleotides was carried out on a sample set of human exons and introns. It is shown that all the periodicities researched, including the three nucleotides period, are random in introns, whereas in exons the 3 periodic regularity is much stronger. The periods that are not multiples of 3, however, are also random in exons. The two nucleotides periodicity, which is, according to the literature, over-represented in introns, appears to be also random in the case under study. The results are important for the development of the algorithms for the coding regions search in DNA, and for the understanding of the global statistic regularities in human genome.