Effect of X-ray irradiation on ancient DNA in sub-fossil bones - Guidelines for safe X-ray imaging.
Sub-fossilised remains may still contain highly degraded ancient DNA (aDNA) useful for palaeogenetic investigations. Whether X-ray computed [micro-] tomography ([μ]CT) imaging of these fossils may further damage aDNA remains debated. Although the effect of X-ray on DNA in living organisms is well documented, its impact on aDNA molecules is unexplored. Here we investigate the effects of synchrotron X-ray irradiation on aDNA from Pleistocene bones. A clear correlation appears between decreasing aDNA quantities and accumulating X-ray dose-levels above 2000 Gray (Gy). We further find that strong X-ray irradiation reduces the amount of nucleotide misincorporations at the aDNA molecule ends. No representative effect can be detected for doses below 200 Gy. Dosimetry shows that conventional μCT usually does not reach the risky dose level, while classical synchrotron imaging can degrade aDNA significantly. Optimised synchrotron protocols and simple rules introduced here are sufficient to ensure that fossils can be scanned without impairing future aDNA studies.
Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.|Institute for Archaeological Sciences, Archaeo- and Palaeogenetics, University of Tübingen, Tübingen, Germany.
Alexander
A
Immel
Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.|European Synchrotron Radiation Facility, Grenoble, France.
Adeline
A
Le Cabec
Institute of Clinical Molecular Biology, Kiel University, Kiel, Germany.
Marion
M
Bonazzi
Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.
Alexander
A
Herbig
Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
Heiko
H
Temming
Institute for Archaeological Sciences, Archaeo- and Palaeogenetics, University of Tübingen, Tübingen, Germany.|Senckenberg Center for Human Evolution and Palaeoenvironment, University of Tübingen, Tübingen, Germany.
Verena J
VJ
Schuenemann
Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.
Kirsten I
KI
Bos
Institute for Archaeological Sciences, Archaeo- and Palaeogenetics, University of Tübingen, Tübingen, Germany.
Frauke
F
Langbein
Senckenberg Center for Human Evolution and Palaeoecology, Palaeoanthropology, University of Tübingen, Tübingen, Germany.
Katerina
K
Harvati
CNRS UMR 7041 ArScAn, Equipe Archéologies environnementales, F-92023 Nanterre Cedex, France.
Anne
A
Bridault
Association départementale pour la recherche archéologique en Savoie, F-73230 Saint-Alban-Leysse, France.
Gilbert
G
Pion
Centre for the Archaeology of Human Origins, Archaeology Department, University of Southampton, Southampton, UK.|Unité Histoire naturelle de l'Homme préhistorique (UMR 7194), Sorbonne Universités, Muséum national d'Histoire naturelle, CNRS, Paris, France.
Marie-Anne
MA
Julien
Department of Stone Age, Institute of Archaeology, National Ukrainian Academy of Science, Kiev, Ukraine.
Oleksandra
O
Krotova
Senckenberg Center for Human Evolution and Palaeoenvironment, University of Tübingen, Tübingen, Germany.
Nicholas J
NJ
Conard
Institute for Archaeological Sciences, Archaeozoology, University of Tübingen, Tübingen, Germany.
Susanne C
SC
Münzel
Department of Geosciences, Palaeobiology, University of Tübingen, Tübingen, Germany.
Dorothée G
DG
Drucker
Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.|Department of Anthropology, University of Toronto, Toronto, Canada.
Bence
B
Viola
Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
Jean-Jacques
JJ
Hublin
European Synchrotron Radiation Facility, Grenoble, France.
Paul
P
Tafforeau
Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.|Institute for Archaeological Sciences, Archaeo- and Palaeogenetics, University of Tübingen, Tübingen, Germany.|Senckenberg Center for Human Evolution and Palaeoenvironment, University of Tübingen, Tübingen, Germany.
Johannes
J
Krause
D000818:Animals; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D000072441:DNA, Ancient; D004307:Dose-Response Relationship, Radiation; D005580:Fossils / Q000000981:diagnostic imaging*; D017356:Synchrotrons; D014965:X-Rays
D000072441:DNA, Ancient