Summary: Genome Growth and the
Evolution of the Genotype­Phenotype Map
Lee Altenberg ?
Institute of Statistics and Decision Sciences,
Duke University, Durham, NC 27708­0251 U.S.A
The evolution of new genes differs fundamentally from evolution through allelic
substitution, because it is through the evolution of new genes that the genome acquires
its degrees of freedom for genetic variability. Selection in the evolution of new genes can
therefore shape the nature of variability in the genome. An analysis of this effect reveals
an evolutionary mechanism that can affect the variational properties of the genome and
its evolvability. One consequence of selective genome growth is a form of genic selec­
tion: genes with large potential for generating new useful genes when duplicated ought
to proliferate in the genome, rendering it ever more capable of generating adaptive vari­
ants. A second consequence is that alleles of new genes whose creation produced a
selective advantage may be more likely to also produce a selective advantage, provided
that gene creation and allelic variation have correlated phenotypic effects. A fitness dis­
tribution model is analyzed which demonstrates these two effects quantitatively. These
are effects that select on the nature of the genotype­phenotype map. New genes that
perturb numerous functions under stabilizing selection, i.e. with high pleiotropy, are
unlikely to be advantageous. Therefore, genes coming into the genome ought to ex­

Source: Altenberg, Lee - Department of Information and Computer Science, University of Hawai'i at Manoa

Collections: Computer Technologies and Information Sciences