Theoretical Models for Heterogeneity of Base Composition
in DNA
R.A. Elton
Journal of Theoretical Biology 45, 533--553 (1974)
Abstract
Data on DNA base composition heterogeneity and molecular size,
mainly from bacteria, are compiled from the literature. A
series of theoretical models of increasing complexity is put
forward, and it is concluded that the data support a model
in which the DNA consists of a sequence of "segments" with
different underlying base compositions. Estimates of mean
segment length and variance of G+C content are made. The
possibility that the excess heterogeneity above random results
from variation in the composition of coded proteins is considered
and rejected. It is concluded that the heterogeneity is probably
caused by variations in the relative use of synnonymous codons
in different genes.
