Quantum Patterns of Genome Size Variation in Angiosperms

Abstract

Aims: The discontinuous pattern of genome size variation in angiosperms is an unsolved problem related to genome evolution. In this study, we introduced a genome evolution operator and solved the related eigenvalue equation to deduce the discontinuous pattern. Background: Genome is a well-defined system for studying the evolution of species. One of the basic problems is the genome size evolution. The DNA amounts for angiosperm species are highly variable, differing over 1000-fold. One big surprise is the discovery of the discontinuous distribution of nuclear DNA amounts in many angiosperm genera. Objective: The discontinuous distribution of nuclear DNA amounts has certain regularity, much like a group of quantum states in atomic physics. The quantum pattern has not been explained by all the evolutionary theories so far and we shall interpret it through the quantum simulation of genome evolution. Methods: We introduced a genome evolution operator H to deduce the distribution of DNA amount. The nuclear DNA amount in angiosperms is studied from the eigenvalue equation of the genome evolution operator H. The operator H is introduced by physical simulation and it is defined as a function of the genome size N and the derivative with respect to the size. Results: The discontinuity of DNA size distribution and its synergetic occurrence in related angiosperms species are successfully deduced from the solution of the equation. The results agree well with the existing experimental data of Aloe, Clarkia, Nicotiana, Lathyrus, Allium and other genera. Conclusion: The success of our approach may infer the existence of a set of genomic evolutionary equations satisfying classical-quantum duality. The classical phase of evolution means it obeys the classical deterministic law, while the quantum phase means it obeys the quantum stochastic law. The discontinuity of DNA size distribution provides novel evidences on the quantum evolution of angiosperms. It has been realized that the discontinuous pattern is due to the existence of some unknown evolutionary constraints. However, our study indicates that these constraints on the angiosperm genome essentially originate from quantum.