Jump to content


- - - - -

PCR program


2 replies to this topic

#1 hobglobin

    Growing old is mandatory, growing up is optional...

  • Active Members
  • PipPipPipPipPip
  • 15,036 posts

Posted 17 August 2009 - 03:18 AM

Hi,

I got a PCR program that has as final extension step (at least I interpret it as extension step) 30 minutes at 60°C. Normally I use 10 minutes at 72°C...
So what is the aim of this long time at 60 degrees?

(Complete program:
3 min 94°C
30 s 94°C
90s 58°C
60s 72°C (loop back to step 2 30 times)
30 min 60°C

Thanks for any ideas...

One must presume that long and short arguments contribute to the same end. - Epicurus
...except casandra's that belong to the funniest, most interesting and imaginative (or over-imaginative?) ones, I suppose.

#2 noelmathur

    Enthusiast

  • Active Members
  • PipPip
  • 71 posts

Posted 17 August 2009 - 06:07 AM

Frankly, quiet odd to my knowledge. I always do as you say.

But why do you need annealing time to be for 90sec?, 30 sec is enough, right?

Would love to hear what others have to say.

#3 swanny

    Veteran

  • Active Members
  • PipPipPipPipPip
  • 552 posts

Posted 17 August 2009 - 05:16 PM

AT 60 degrees, most of the thermophilic polymerases would only work very slowly. Perhaps it's there for some kind of proofreading (wouldn't work with Taq, though), or to ensure all amplicons are full length (but your point of 10 minutes @72 deg would do the same thing).
Be nice to your bureaucrats: they control your budgets...





Home - About - Terms of Service - Privacy - Contact Us

©1999-2011 Protocol Online, All rights reserved.