Freezing damage DNA?

[Paul N Hengen]

 In article <416ffu$8ub at enterprise.sct.gu.edu.au> 
 "h.woo" <h.woo at sct.gu.edu.au> writes:

| It seems that freezing and thawing repeatedly does affect DNA, as far as 
| using genomic DNA as PCR template is concerned. I keep my genomic DNA 
| stock solutions at 4C.

I've heard the reasons why multiple freeze-thaw cycles of PCR primer stocks
could limit the PCR, but I haven't heard anything about genomic DNA samples.
How could this happen? Are the samples already restriction digested or just
stored as genomic DNA isolates?

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* Paul N. Hengen, Ph.D.                           /--------------------------/*
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