Touch-down PCR is another modification. Its characteristics include:

Touch-down PCR is another modification. Its characteristics include: Correct Answer Primer annealing is done at higher temperatures initially

It is done in order to overcome the slight mismatch which takes place at lower temperatures. For this, initially the temperature is kept very high and it is reduced in further cycles. As the temperature is reduced, a stage is reduced at which correct primer-template binding is possible but not the incorrect one. In this, in the earlier cycles more stringent conditions are there and in later cycles less stringent conditions are there.