Epigenetic differences arise during the lifetime of monozygotic twins.
Proc Natl Acad Sci U S A. 2005 Jul 26;102(30):10604-9. doi: 10.1073/pnas.0500398102. Epub 2005 Jul 11.
Proc Natl Acad Sci U S A. 2005.
PMID: 16009939
Free PMC article.