False Positive PCR Results from DNA Contamination

Symptom

No-template controls (NTC) or negative controls show unexpected amplification. Particularly problematic in sensitive applications like human identification qPCR where trace DNA contamination produces false positives.

1. 1 Human DNA contaminants present in plastic consumables from manufacturing process
2. 2 Sealing films lacking ethylene oxide treatment (per ISO 18385) for sensitive human DNA applications
3. 3 Cross-contamination between wells due to improper sealing allowing aerosol transfer

1. 1 Request Certificate of Analysis proving lot tested negative for human DNA contamination
2. 2 For human identification applications, ensure sealing films are ethylene oxide-treated per ISO 18385 requirements
3. 3 Verify all wells properly sealed; consider tube strips with attached independent caps to prevent cross-contamination

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