Dimeric Diagnostic DNA Arrays for Pathogen Detection and Identification

A 7 times higher signal intensity was obtained for the dimeric probes D and the dimeric probes with a 10-adenine spacer DA compared to conventional monomeric probes M.

Invention Summary:

Rutgers scientists have developed a unique and pioneering technology for detection and identification of important pathogens in the form of a macroarray diagnostic technology with enhanced detection sensitivity and small reduction in specificity using repeat sequence probes (dimers). We continue to have positive results and improvements, and believe the next stage will focus on refinement, development of a portable ‘kit’, and pathogen quantification, among others.

To date, Dr. Zhang has produced membrane-based macroarrays that include five types of oligonucleotide probes. The probes were designed based on the internal transcribed spacer sequences of rRNA genes of four important microbial pathogens of cereals, turfgrass, and other plants, i.e., Rhizoctonia solani, Pythium aphanidermatum, Fusarium solani, and F. oxysporum, to compare studied for each type of strains were monomers (M; 20-24nt), monomers with a 10-adenine tail (M-A10), monomers with a 20-adenine tail (M-A20), dimers (D; 40-48nt), and dimers with a 10-adenine spacer (DA). Among all probes, D and DA probes displayed significantly higher sensitivity than the M, M-A10, and M-A12 probes. The dimeric probes D also had lower signal variability, thereby increasing the macroarray signal uniformity. The developed method is rapid and can be useful for early human, animal, or plant diagnosis, as well as for water and environmental analysis.

Numerous additional probes are in the process of being designed and tested as part of this continuing program. 

Market Applications:

• Pathogen Detection
• Human, Animal, and Plant (agricultural crops) Diagnostic
• Water and Environmental Analysis 

Advantages:

• High sensitivity allows early disease diagnosis when only trace amounts of target microbes are present in a sample. Thus, pathogen detection be achieved prior to the onset of symptoms.
• Versatile diagnostic method that can be used for human, animal, and plant (fruits, vegetables, crops) diagnosis; and for water, soil, and environmental analysis.
• The dimeric probes reliably detected 0.01 fg target genomic DNA, which is lower than the detection limits of most currently available molecular diagnostic methods, such as real-time PCR.
• The developed membrane-based macroarray offers a reusable, cost-efficient and flexible platform compared to glass-based, high-density  microarrays.
• Able to detect multiple pathogens simultaneously.
• Can be used to detect so me hard to diagnose infections such as a staph infection.
• The developed method is faster (less than 12 hours) than the traditional culture-based diagnostic method, which often takes days or weeks. Expectation is that it could be as rapid as 6 hours.
• Can be tailored to portable diagnostic kit that can be used to detect pathogens directly in the field.

Intellectual Property & Development Status:

• US 9,222,125. This technology is available for licensing and/or sponsorship of future developments
• Program currently funded in part by the United States Golf Association