Article ID Journal Published Year Pages File Type
9469844 Journal of Theoretical Biology 2005 8 Pages PDF
Abstract
Epigenetic differentiation is the potentially heritable changes in levels of gene expression not caused by DNA sequence changes. Here, a classification scheme of mutations and epimutations is introduced, enabling a simple analysis of mutation and epimutation load in haploid and diploid organisms. It is found that the deleterious effect of epimutations is mainly determined by epimutation rate and degree of reversibility. Inherited epimutations have the same fitness consequences as inherited mutations. With complete reversibility and no inheritance, then epimutations have the same fitness consequences as somatic mutations. It is argued that organisms with somatic inheritance may experience more genetic load than organisms without somatic inheritance due to inherited epimutations in the former. This may partly explain the maintenance of soma/germ differentiation in many life forms. It is also argued that masking of deleterious somatic mutations may not necessarily explain the evolution of diploidy in life forms with inherited epimutations.
Related Topics
Life Sciences Agricultural and Biological Sciences Agricultural and Biological Sciences (General)
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