• Furthermore, we show that accurate sex identification of highly degraded remains can be performed in the presence of substantial amounts of present-day contamination by utilizing the signature of cytosine deamination, a characteristic feature of ancient DNA. (blogspot.com)
  • In previous studies, we suggested that this inhibition is likely a defense mechanism developed by phage phi29 to prevent the action of UDG if uracilation occurs in DNA either from deamination of cytosine or the incorporation of dUMP during viral DNA replication. (nih.gov)
  • Ammonia is toxic to the human system, and enzymes convert it to urea or uric acid by addition of carbon dioxide molecules (which is not considered a deamination process) in the urea cycle, which also takes place in the liver. (wikipedia.org)
  • DNA ligase then forms a phosphodiester bond to seal the resulting nicked duplex product, which now includes a new, correct cytosine (Base excision repair). (wikipedia.org)
  • Active demethylation in mouse zygotes involves cytosine deamination and base excision repair. (uni-muenchen.de)
  • Cytosine deamination and base excision repair cause R-loop-induced CAG repeat fragility and instability in Saccharomyces cerevisiae . (bvsalud.org)
  • This tandem displacement mechanism allows DddA to locate a target cytosine without flipping it into the active site. (anl.gov)
  • The resulting abasic site is then recognised by enzymes (AP endonucleases) that break a phosphodiester bond in the DNA, permitting the repair of the resulting lesion by replacement with another cytosine. (wikipedia.org)
  • selection of hypermutable (mutator) increased risk for deamination [email protected] alleles based on alterations in DNA because of the production of reactive repair genes. (cdc.gov)
  • This method, thus, appears only appropriate for the analysis of ancient methylomes from very well preserved samples, where both DNA fragmentation and deamination have been limited. (ku.dk)
  • It has been known for several decades that the pattern of distribution of methyl cytosines is not equal in all tissues in a multicellular organism and that it exhibits tissue specificity (Razin and Szyf 1984 ). (biomedcentral.com)