Thermal cycling by positioning relative to fixed-temperature heat source

A thermal cycling system for performing a polymerase chain reaction amplification protocol comprising multiple cycles of three temperature-dependent stages of template denaturation, primer annealing and primer extension that constitute a single cycle of PCR, the thermal cycling system comprising:

• a) a heat source that is set at a fixed temperature;
• b) a metal sleeve capable of receiving a reaction vessel containing material upon which a polymerase chain reaction amplification protocol is to be performed, wherein the sleeve includes a temperature-sensing means for sensing the temperature of the sleeve;
• and
• c) moving means operatively associated with the sleeve for altering the relative position of the heat source and the sleeve based on the temperature of the sleeve sensed by the temperature-sensing means, the thermal cycling system arranged and configured such that,
• i) in a first configuration the relative positions of the sleeve and the heat source, with respect to each other, are such that the sleeve achieves and maintains a first temperature for carrying out template denaturation on the material;
• ii) in a second configuration the relative positions of the sleeve and the heat source, with respect to each other, are adjusted such that the sleeve achieves and maintains a second temperature for carrying out primer annealing on the material;
• and
• iii) in a third configuration the relative positions of the sleeve and the heat source, with respect to each other, are adjusted such that the sleeve achieves and maintains a third temperature for carrying out primer extension on the material.