Which DNA is good for PCR for amplify a certain sequence? cDNA or genomic DNA ? - (Jan/04/2009 )

i have designed a pair of primer and i want to amplify for the wanted sequence. I am wondering using total RNA to RT the cDNA for PCR or direct PCR by using genomic DNA.

Which one is better ? Why?

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genomic DNA - fewer steps (DNA purification, then PCR), but probably will be more difficult to perform the PCR because there will be fewer copies of your target sequence. However, if you have introns in your gene they will be included.

cDNA - more steps and requires cleaner handling (RNA purification, then RT reaction, then PCR), but PCR might be easier. Target will not contain introns.

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