Patent ID: 7488578

Claim:
A method for detecting DNA point mutations utilizing capture/target DNA hybrids at hybridization positions, the capture/target DNA hybrids formed by binding target DNA to be detected to capture DNA immobilized position-specifically on a DNA chip, the method comprising, performing a washing phase and a measurement phase alternately at different temperatures, the washing phase including: a) passing a washing liquid at a controlled flow rate over the DNA chip, b) changing the temperature at the hybridization positions in a defined manner as a function of time, with a continuous increase in temperature as a function of time being carried out in ramps with subsequent temperature holding times, and c) melting the capture/target DNA hybrids temperature-dependently, and removing melted target DNA from the hybridization positions using the flowing washing liquid, such that non-melted target DNA remains on the DNA chip, the measurement phase including: d) stopping the flow of washing liquid during the temperature holding times, e) position-specifically detecting the non-melted target DNA at a current temperature of the temperature holding time, and f) analyzing signals according to a predetermined program, the analyzed signals being used to detect the DNA point mutations.