Physically, the somatic epitype corresponds to changes in DNA methylation, oxidative damage (replacement of GTP with oxo-8-dGTP), or changes in DNA-chromatin structure that are not reversed by normal cellular or nuclear repair mechanisms. Somatic epitypes alter gene expression levels without altering the amino acid sequence of the expressed protein.
Physically, somatic epitypes involve modifications to DNA methylation, oxidative damage (replacement of GTP with oxo-8-dGTP), or changes in DNA-chromatin structure that are not restored by normal cellular repair processes. This leads to altered gene expression levels without affecting the protein's amino acid sequence.