# Commission Directive 2006/56/EC of 12 June 2006 amending the Annexes to Council Directive 93/85/EEC on the control of potato ring rot, Division 6.3.4

Extent: E+W+S+N.I.

For all new findings/cases verify authenticity of the PCR amplicon by performing restriction enzyme analysis on a sample of the remaining amplified DNA by incubating at the optimum temperature and time with an appropriate enzyme and buffer (see Appendix 6). Resolve the digested fragments by agarose gel electrophoresis as before and observe characteristic restriction fragment pattern under UV transillumination after ethidium bromide staining and compare with the undigested and digested positive control.
Interpretation of the PCR test result:
The PCR test is negative if the C. m. subsp. sepedonicus-specific PCR amplicon of expected size is not detected for the sample in question but is detected for all positive control samples (in case of multiplex PCR with plant specific internal control primers: a second PCR-product of expected size must be amplified with the sample in question).
The PCR test is positive if the C. m. subsp. sepedonicus-specific PCR amplicon of expected size and restriction pattern (when required) is detected, providing that it is not amplified from any of the negative control samples. Reliable confirmation of a positive result can also be obtained by repeating the test with a second set of PCR primers (section 9.3).
Contamination may be suspected if the expected amplicon is obtained from one or more of the negative controls.

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Source: https://www.legislation.gov.uk/eudr/2006/56/annex/I/division/6/division/6.3/division/6.3.4 (the official version)
Page: https://openlegislation.uk/eu-directive-2006-56/annex-I/division-6/division-6.3/division-6.3.4
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.