| Problem |
Possible Cause |
Solution |
| Little or no PCR product is detected. |
- A PCR component is missing or degraded.
|
- Run a positive control to ensure components are functioning.
|
|
| Little or no PCR product is detected. |
- No leaf tissue extract is added to the PCR reactions.
|
- Check the performance of liquid handler. Prime the system if needed. Adjust the aspiration distance of the pipettors in the
extraction plate.
|
|
| Little or no PCR product is detected. |
- PCR reaction is inhibited due to contaminants in leaf tissue extract.
|
- Use less extract or dilute the extract with 50:50 mix of Extraction and Dilution Solutions and repeat PCR.
|
|
| Little or no PCR product is detected. |
- The mixing of Dilution Solution with leaf tissue DNA extract is not sufficient due to inefficient mixing by the Liquid Handler and/or the clogging of the pipette tip by the tissue samples.
|
- Increase the aspiration and dispensing speed and/or cycle times in the mixing steps. Increase the aspiration distance
of the pipette tips in the mixing steps to avoid sucking up the tissue by the pipettors.
|
|
| Little or no PCR product is detected. |
- Genomic DNA is sheared when
mix the solution with the pipettor.
|
- Reduce the aspiration and
dispensing speed and/or cycle
times in the mixing steps. It is
critical for amplifying the large
genomic DNA fragments.
|
|
| Little or no PCR product is detected. |
- Too few amplification cycles are
performed.
|
- Increase the number of cycles
(5-10 additional cycles at a
time).
|
|
| Little or no PCR product is detected. |
|
- Refer to the Technical Bulletin of
Extract-N-Amp Plant PCR Kits.
|
|
| Negative control shows a PCR product or “false positive” results are obtained. |
- Reagents are contaminated.
|
- Use new labware and new batch
of reagents. Test a reagent
blank without DNA template to
determine if the reagents used
in extraction or PCR are
contaminated.
|
|
* All trademarks are the property of their respective owners. Where applicable,
the PCR process is covered by patents owned by Roche Molecular Systems,
Inc., and F. Hoffman-LaRoche, Ltd.