DNA from sera - isolation of genomic DNA from platoregistry human sera (Apr/16/2002 )
I am seeking procedures and/or advice on how to isolate human genomic DNA from platoregistry sera. The sera is lymphocytes that have been frozen for 35-40 years but are not dessicated.
Will the isolated DNA be stable in small quantities for a long period of time? How will I be able to store 2-4 ug of pure DNA? What type of buffer? If buffer concentrates, what will happen to the DNA? Thanks for your help.
You may or may not be able to get much DNA from these frozen lymphocyte samples. At what temperature are the samples stored? The colder the better. I have had success with isolating DNA from whole blood and lymphocytes frozen for 2 years at -80C. 35-40 years may be pushing your luck a bit. You could probably use an organic or salt method (although some salt methods don't have the best long term stability of DNA). You may also want to check out commercial kits as well.
Once you get the DNA isolated, it should be more stable than in the cells. Probably your best bet for storage is in TE (at least for stability). If the buffer gets concentrated, it won't effect your DNA but EDTA will chelate magnesium and so may inhibit PCR if the solution becomes concentrated.