MRSA Genotyping Array
GenArraytion has developed a genotyping array based on genetic similarities and differences in the whole genome sequence data from ten Staphylococcus strains. 700 different specific DNA sequences were synthesized on a microarray to generate highly discriminating hybridization-based signatures to provide high fidelity, treatment-oriented discrimination. Purified DNA from eight Staphylococcus aureus strains was purchased (genome sequence is available for only three of the eight, the other five have no prior genetic information) and amplified and labeled using whole genome amplification. The product was hybridized to the genotyping array. Unique hybridization patterns were obtained for each of the eight strains.
A subset of the data are presented above in the 3-D plot using the results for sequenced Mu50 (hospital acquired MRSA, vancomycin resistant), USA300 (community acquired MRSA) and the non-sequenced MRSA Strain 328 (ATCC#33591). The location of each data point is a function of its hybridization intensity (indicating presence or absence) from hybridizations with labeled DNA from each of the three target organisms. Sequences present in only one organism fall along the axes. Sequences present in two of the three organisms appear on the walls of the graph. Sequences found in all three strains were removed for clarity of visualization.
A subset of the data are presented above in the 3-D plot using the results for sequenced Mu50 (hospital acquired MRSA, vancomycin resistant), USA300 (community acquired MRSA) and the non-sequenced MRSA Strain 328 (ATCC#33591). The location of each data point is a function of its hybridization intensity (indicating presence or absence) from hybridizations with labeled DNA from each of the three target organisms. Sequences present in only one organism fall along the axes. Sequences present in two of the three organisms appear on the walls of the graph. Sequences found in all three strains were removed for clarity of visualization.
© 2008 GenArraytion, Inc. All Rights Reserved.
The data to the left clearly indicate that Strain 328 shares genetic elements with hospital-acquired and community-acquired MRSA strains and points to genetic elements that may be of concern in individuals infected with this strain. The GenArraytion Staph genotyping array provides a rapid, reproducible molecular profile for eight S. aureus strains, most of which were previously uncharacterized at the molecular level. These results demonstrate that targeted micro-sequencing can provide rapid, informative DNA sequence-based identification and characterization of strains that have not been characterized at the molecular level. This approach can be used to detect emerging and genetically engineered threats to public health. Partial matches to common strains may indicate genetic drift, while the appearance of virulence factors and/or antibiotic resistance elements in the absence of markers for organisms known to contain these factors provides an indication of genetic engineering. These methods enable reliable identification of infectious agents and characterization antibiotic susceptibility needed to effectively diagnose and treat local, regional and pandemic infectious disease outbreaks.
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