The primer and NTPs are always in large excess in the pcr reaction so I would expect to get the correct product. Because there is a lot too much primer I would also expect increased annealing to other regions of the genome resulting in extra non specific bands. It is alsp probable that you will get a strong primer dimer amplimer resulting in a blurred band at about 50 bp which will make the pcr look a bit messy

Thank you for your reply Paul Rutland . I did not get ay band expect for the primer dimer.

If you accidentally used 20X too much primer, then the reaction would probably fail. I've seen it happen when someone didn't dilute out the stock 100 micro molar primer to a 10 micro molar working solution. No amplification from any DNA samples.

But at least it's an easy fix to try again!

Desired reaction will be completed. But, primer dimer will occur after gel run due to use of high concentration of primer.

How did your reactions turn out? In my experience, the reactions don't work and you get a massive primer dimer band.

In my lab, we keep the stock solutions in the original tubes and make the working dilutions in 1.5 ml snap top tubes so it's easy to tell the difference between stock and working. Everyone has their own diluted primers too, which helps to prevent accidental contamination of the stocks.