I have been having lots of troubles gettign robust PCR reactions to work from cDNAs that I have stored in the -20. I have checked the RNA quality by gel electrophoresis and get nice rRNA bands and no degredation. However, depending on the day some of my cDNA give me products and some do not. Is there a way to check the quantity and quality of cDNA? Can you spec it and get anything measurable? can you run a gel?