Question

Difference between primers is greater than 5 degrees

Answer 1

As a rule of thumb, for primers up to 20 bases in lenght, take 2°C For each A or T and 4°C for each C or G. This will be accurate enough for many cases.

The difference of Tm < 5oC of two primers can let you easily decide/choose a Ta (annealing temperature) for both primers to anneal to the template.

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