I have seen that embryonic stem cells are shown to use homologous repair for double strand breaks rather then non-homologous end joining (NHEJ). [1]

I am wondering if something also happens to a cell's usage of certain repair mechanisms after diversifying.

For instance, is there any evidence that two cells in the same lineage but of different ages (one from a person who is 20, another from someone who is 80) use different ratios of repair mechanisms? Has there been any research on this or is there any indirect data that could support such an idea?

  • $\begingroup$ The mechanism of DNA repair depends on the stage of cell cycle. Different cell types spend different relative times in different stages of cell cycle and so their preference for the DNA repair mechanism varies. $\endgroup$ – WYSIWYG Dec 10 '15 at 15:53
  • $\begingroup$ Yes I know this but I am asking about two cells of the same type but in organisms of different ages. Has there been any comparison between two cells that are the same type, from the same species, but from two organisms that are at different stages of life to see if there is a difference in what repair mechanism type that they prefer? $\endgroup$ – FrankyG Dec 10 '15 at 15:55
  • $\begingroup$ I haven't come across any such studies but if the cell is self renewing at the same rate at both the ages (and has no other accumulated mutations), the preference ratio should remain the same. $\endgroup$ – WYSIWYG Dec 10 '15 at 15:59
  • $\begingroup$ I'm mainly wondering since we know that mutations occur more often as an organism ages and if perhaps there is more at play than telomere shortening, build-up of junk, etc. The most I can find is this study nature.com/cr/journal/v18/n1/full/cr2007111a.html However it really focuses on the decision between choosing NHEJ or HR and pretty much said what you said about there being differences during cycle and between types of cells. It'd be interesting to study but right now I can't find any evidence that would lead me to think it is happening or deserves investigation. $\endgroup$ – FrankyG Dec 10 '15 at 16:04
  • $\begingroup$ Also this fasebj.org/content/14/10/1325.full, but other than that I can't really find anything that could lead someone to support this idea. $\endgroup$ – FrankyG Dec 10 '15 at 16:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.