Query posted regarding degrading DNA
>>We would like to be able to keep the DNA samples for at least several
>>years without significant degradation. Any comments or suggestions
>>regarding suitable storage techniques would be appreciated.
It seems unlikely that your DNA is actually degrading during storage at -70C.
Try heating the DNA to 65C for 15min to kill any nucleases before adding any
restriction enzyme buffer. In my experience, once you add the RE buffer, any
contaminating nucleases get activated. The Chloroform idea is also good if you
must store at 4C, but it is not a permanent solution.
Best wishes, David.