Some time ago, I suggested that people could post abstracts of
diagnostics papers here, in order to stimulate more on-topic
discussion. Here is an abstract from my own laboratory, of a paper
publ;ished in the Proceedings of the Diagnostics in Crop Protection
conference held in Warwick, UK earlier this month.
DETECTION OF POTATO VIRUS Y USING THE LIGASE CHAIN REACTION
(LCR), IN COMBINATION WITH A MICROTITRE PLATE BASED METHOD
FOR PRODUCT DETECTION
K J O'DONNELL, E CANNING and L G A YOUNG
Scottish Agricultural Science Agency, East Craigs, Edinburgh, EH12 8NJ, UK
email: odonnell at sasa.gov.uk
ABSTRACT
The Scottish Agricultural Science Agency (SASA) carries out diagnostic
tests for viruses on potato leaf and tuber samples in support of the Scottish
Seed Potato Classification Scheme. Currently, routine detection of potato
viruses in submitted leaf samples is carried out using ELISA (enzyme-linked
immunosorbent assay). However, ELISA is not sufficiently sensitive
to consistently detect the small amounts of virus present in primary infected
tubers. In this case, the dormancy of the tubers must first be broken and then
the resulting plants tested by ELISA, a process which can take several weeks.
In order to reduce this period we have evaluated nucleic acid amplification
techniques which can theoretically achieve the level of sensitivity necessary
for virus detection directly from tubers. In this paper we report on the
development of an assay for PVY based on the ligase chain reaction (LCR),
a method based on the ligase-mediated exponential amplification of DNA probes
specific to target DNA (or cDNA) of the pathogen. We have combined the
LCR assay with a microtitre plate based detection system which removes the
need to run electrophoresis gels to detect products of the assay. This method
has the possibility of combining the sensitivity and specificity of nucleic
acid-based techniques with the automation of ELISA. Preliminary results are
shown which compare the performance of LCR with the standard ELISA method.
Dr Kevin O'Donnell "Nature is not cruel, only
Diagnostics and Molecular Biology pitilessly indifferent."
SASA - Richard Dawkins
Edinburgh
