title: Investigation of neutron-induced damage in DNA by atomic force microscopy: experimental evidence of clustered DNA lesions.
abstract: Using atomic force microscopy (AFM), we have investigated neutron-induced DNA double-strand breaks in plasmids in aqueous solution. AFM permits direct measurement of individual DNA molecules with an accuracy of a few nanometers. Furthermore, the analysis of the DNA fragment size distribution is non-parametric, whereas other methods are dependent on the model. Neutron irradiation of DNA results in the generation of many short fragments, an observation not made for damage induced by low-LET radiation. These data provide clear experimental evidence for the existence of clustered DNA double-strand breaks and demonstrate that short DNA fragments may be produced by such radiations in the absence of a nucleosomal DNA structure.
authors.affiliation: Department of Radiation Medicine, Georgetown University Medical Center, Washington, DC 20007, USA.
authors.forename: D
authors.initials: D
authors.lastname: Pang
authors.forename: B L
authors.initials: BL
authors.lastname: Berman
authors.forename: S
authors.initials: S
authors.lastname: Chasovskikh
authors.forename: J E
authors.initials: JE
authors.lastname: Rodgers
authors.forename: A
authors.initials: A
authors.lastname: Dritschilo
mesh_terms: D004247:DNA / Q000737:chemistry / Q000528:radiation effects* / Q000648:ultrastructure; D004249:DNA Damage; D066298:In Vitro Techniques; D018625:Microscopy, Atomic Force; D009502:Neutrons / Q000009:adverse effects*; D010957:Plasmids / Q000737:chemistry / Q000528:radiation effects / Q000648:ultrastructure; D012062:Relative Biological Effectiveness; D012996:Solutions; D014867:Water
chemical_list: D012996:Solutions; D014867:Water; D004247:DNA