Detecting a pathogen by recognizing its genome typically relies on the binding of relatively long, unique nucleotide sequences to complementary “test” strands. The problem is that this approach requires a large amount of DNA, which is why the method requires the use of the PCR, an amplification method.

However, in simulations by Curk et al. (PNAS (2020) 117, 8719–8726) an alternative approach has been proposed, which exploits the fact that the genomes of different pathogens differ in the frequency of occurrence of short nucleotide sequences of length 10 to 20 bases. DNA-coated surfaces can be designed that bind super-selectively to nucleotide sequences that contain many repeats of such short target sequences.

Prof. Eiser will present experiments that demonstrate that the proposed method not only works in practice, but is able to distinguish between closely related pathogens (Xu et al., PNAS (2023) 120 (37), e2305995120).