The determination of the right gene sequence in nucleic acid-based biosensor development is vital for distinguishing the pathogenic strains from the non-pathogenic ones. For the detection of general E. coli, 16s rRNA or uidA gene are the most common biorecognition elements among the selected articles. These genes, however, do not allow distinguishing between E. coli and Shigella spp., which share very similar genetic material to E. coli. Other genes such as yaiO, MalB or ybbW that show higher specificity towards E. coli can be considered in the future development of nucleicacid-based biosensors targeting these bacteria. The most specific detection of STEC should be based on either stx1 or stx2 genes coding for toxin production which has been studies by several researchers for the development of STEC biosensors. Usually, the eaeA gene, coding for intimin production, has been targeted, which is not sufficient to recognise all strains responsible of serious illnesses. Currently, there are several studies actively targeting the identification of more virulence factors of STEC and the development of multiplex biosensors capable of detecting several genes simultaneously.