Siemens of Munich, Germany, has received US Patent No. 7,488,578, “Method for detecting DNA point mutations (single nucleotide polymorphism (SNP) analysis) and associated arrangement.” The patent claims the following method. A liquid DNA sample to be analyzed is guided over a DNA chip in a defined time course. After successful hybridization, the temperature is modified in a defined manner under low stringency conditions so that scavenger/target DNA hybrids are melted. The melting of the scavenger/target DNA hybrids is detected and evaluated according to the temperature.