Suggested Model for the Origin of Mosaic Structure of DNA

Abstract

In view of the critical behavior exhibited by a statistical model describing a one dimensional crystal containing isotopic impurities and the fact that for impurity mass parameter 3 times the host mass the critical temperature can attain very high values, we suggest that the mosaic structure displayed by certain nucleic acids (DNA) of eukaryotic organisms might have had its origins in a phenomenon of condensation of codons ocurred at prebiotic conditions. An appropriated map of that model onto some of the DNA features allows one to predict power law behavior for both correlation functions and exons size distribution in binary sequences of nucleotides which are distinguished by their protein coding or noncoding functions. Preliminary studies of these quantities performed on intron-containing sequences from GenBank are presented here.