Primer BLAST - (Jul/31/2012 )

how u know ur primers set that u design is specific to ur target sequences by using blastn ?

and why when amplificating cDNA you need to design primes that cross the exon boundaries ?and if u know any articals that tell the reasen behind that..

what i know is that to be able to distinguish between gDNA produect AND cDNA PRODUCTS .

1. longer primers provide higher specificity. for example, if you have a primer that has only 3 bases like ATG, then you can imagine its specificity. Generally, a primer length of 25-30 would be enough for a high specificity.

2. you are right. gDNA contains intron so the product would be longer than that from cDNA.