A novel Loop-mediated Isothermal Amplification Method for Screening Detection of Genetically Modified Cotton

Area of Science:

• Agricultural Biotechnology
• Molecular Biology
• Food Safety

Background:

• Japan imports significant cottonseed due to limited domestic production.
• Introduction of genetically modified (GM) cotton seeds necessitates robust detection methods.
• Unauthorized GM cotton poses a risk to the food and feed supply.

Purpose of the Study:

• To develop a simpler, faster, and more cost-effective method for detecting unauthorized GM cotton.
• To provide a qualitative screening method suitable for routine analysis.
• To improve the safety and traceability of imported cottonseed.

Main Methods:

• Loop-mediated isothermal amplification (LAMP) targeting specific GM DNA sequences (P35S, NPTII) and an endogenous gene (sad1).
• Development of a DNA chromatography strip system for visual detection.
• Validation against conventional polymerase chain reaction (PCR) methods.

Main Results:

• The developed LAMP method achieved a limit of detection (LOD) of ≤0.1%, comparable to PCR.
• A novel DNA chromatography system enabled visual detection of amplified DNA at the LOD.
• The method demonstrated simplicity, speed, and cost-effectiveness.

Conclusions:

• The novel LAMP-based detection method is a viable alternative to conventional PCR for GM cotton screening.
• This approach facilitates efficient analysis of GM crops.
• The method is expected to help prevent the unintended environmental dissemination of GM crops.