title: DNA breathes Hoogsteen.
abstract: A recent claim is discussed that Watson-Crick pairs in the naked duplex DNA spontaneously flip into Hoogsteen pairs under ordinary conditions. The claim is considered within the historical retrospective and is put into the broader context of DNA biophysics.
authors.affiliation: Department of Biomedical Engineering; Boston University; Boston, MA USA.
authors.forename: Maxim D
authors.initials: MD
authors.lastname: Frank-Kamenetskii