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Addition of Calf thymus DNA? Why? - (Oct/23/2008 )

Hi there,

i'm about to do a PCR run with Deep Vent from NEB, and they say we should add activated calf thymus DNA to the reaction mix. Why? What are the purpose of adding it? Is it necessary?



If we look at this article, we see that it is actually not required (fig. 7), it seems however to have been used as an "enzyme trap" :

...of an unlabeled DNA trap (to limit interactions
between enzyme and 5'-32P-labeled primer-template molecules
to a single encounter)

see here for the full text.

...note that the DeepVent is more than 10 years old (well NEB update it to DeepVent R - Retake? laugh.gif ) and I suspect (please somebody stop me if I am wrong) that this addition of partially denaturated calf thymus DNA is a protocol artifact, but I'll have to make a few investigations to confirm this; else it depends on the PCR application.


Yes, I saw that it is no more available at NEB.

I still got pretty good amplification with Deep Vent in the past, so I will take a go at it!

Thanks ph3no!