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genomic dna - (Jul/13/2002 )

can i obtain the genomic dna sequence of a gene if i amplify that region with primers obtained from cDNA


This will be hit or miss. If the sequence of your cDNA primers falls on an exon-intron junction you may not get a PCR product. Also, I assume you know nothing about the size of the gDNA which contains your GOI. The expanse of genomic DNA that contains your gene may be very large and not amenable to PCR amplification. What you should do is take your genomic DNA and cut it with a 6 - 8 base restriction endonuclease, run the digest on a agarose gel and perform a Southern blot using your cDNA as a probe. Here you will get an idea of the size of the actual gene and will also get info on any possible psudogenes. You may also extract the gene from a genomic library using you cDNA as a probe.