PNNL-13501 - Pacific Northwest National Laboratory

Summary and Conclusions
The simple 47-target 9-mer array provided a resolving
power that appeared equivalent to a traditional REP-PCR
gel-based analysis.
The total analysis was both simpler and faster than the
traditional gel-based fingerprinting approach. This
method holds great promise for resolving agricultural
pathogens. Some issues with optimization of the probes
(i.e., the specific DNA sequences employed, increased
number of targets) on the array and some background
reactions remain to be resolved.
The data shown is a worst-case scenario; the X. citri
(X axonopodis pv. citri) strains were chosen due to their
high degree of relatedness and the difficulty in
distinguishing individual strains despite the fact they are
from diverse geographic origins (clonal organism).
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Acknowledgements
The contributions of the following PNNL staff members
are gratefully acknowledged: Lucie Fritz (PCR Assays),
Darrell Chandler, Doug Call, Tim Straub (DNA array
analyses), Sharon Cebula, Don Daly, and Kris Jarman
(DNA array statistical analysis and dendrograms).