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DNA copy number-QPCR - (Mar/30/2005 )

Hi,
when I work with DNA to detect copy number changes, what kind of reference should I use? Shall I use GAPDH or a different gene which shows normal in the whole genome?

Is there any difference to design primer for DNA and cDNA? I mean for cDNA, my primers were located in two different exons. How will I design primer for DNA? Thank you very much.

-molcyt-

Dear molcyt,

Are you working with gene expression?


Regards
yong

-yongyk-

Dear Yong,

No, I am working with copy number change detection (amplification, deletion). For this reason I have to work with DNA.

-molcyt-

Hi,

You cannot use cDNA based designed primers for doing qPCR, the reason being the amplicon (from the genomic DNA )likely exceeds the maximun allowed (150 bp) for real-time PCR. If you are using tumors, select a reference gene from a chromosome known to be least affected in the specific tumor you are studying. You may try GAPDH, albumin, beta 2 microglobulin, etc. If you wish, you can design a reference from the above mentioned genes using the corresponding BAC DNA sequences. Try to use an intron while designing. Make sure, there are no SNPs! Hope that helps.

SV

-SVTX-

Dear SVTX,
Thanks a lot for that information.

QUOTE (SVTX @ Apr 2 2005, 04:58 PM)
Hi,

You cannot use cDNA based designed primers for doing qPCR, the reason being the amplicon (from the genomic DNA )likely exceeds the maximun allowed (150 bp) for real-time PCR.  If you are using tumors, select a reference gene from a chromosome known to be least affected in the specific tumor you are studying.  You may try GAPDH, albumin, beta 2 microglobulin, etc.  If you wish, you can design a reference from the above mentioned genes using the corresponding BAC DNA sequences.  Try to use an intron while designing.  Make sure, there are no SNPs!  Hope that helps.

SV

-molcyt-