Konstanz - chemists have developed process that enables gene detection with the naked eye and thus provides an approach for rapid medical tests. The work was published in the journal Angewandte Chemie ().
During the body's own copying process of the genetic material, so-called DNA polymerases read single strand of DNA and recreate complementary counterpart, building block by building block. As the chemists working with Moritz Welter and Andreas Marx were able to show, building blocks can also be built into this process with significantly larger protein attached as cargo. These proteins, which are more than hundred times larger than the DNA building blocks themselves, can be used as markers for the DNA segments.
In the test, sample to be examined is brought together with nucleotide chain that is complementary to the DNA segment sought. This added nucleotide chain contains the attached signal proteins. If the sample contains the desired section, it binds to the nucleotide chain with the signal proteins - even single deviation in the sequence of the DNA building blocks prevents this connection. If, for example, horseradish peroxidase is selected as the signal protein, this makes it possible to recognize the concentration of the DNA segment sought with the naked eye by means of red-brown color.
According to the working group, this test procedure can be implemented at room temperature without laboratory environment and is particularly robust. The method could therefore form the basis for developing test strips for rapid medical tests. With these test strips, among other things, pathogens can be detected without an expensive laboratory test, the scientists believe.