Searching for traces of DNA in environmental samples requires the use of specific laboratories and equipments to avoid cross-contaminations during the analysis.
Nowadays, environmental DNA (eDNA) expertise offers tremendous opportunities for biodiversity monitoring and conservation. Nevertheless, major constraints should be considered when working with eDNA. Indeed, it is essential to ensure that the amplified DNA from an environmental sample is not due to a cross-contamination. For reliability insurance, the eDNA analysis platform should consist of several laboratory rooms, some of which should be equipped with differential pressure and a ventilation system for renewal of the air. Personnel using these laboratories should follow specific practices and wear suitable lab clothes. Failure to comply with these requirements will unavoidably lead to cross-contaminations when the number of analysed samples becomes too high and make the results untrustable.
An environmental DNA analysis platform should include a minimum of 4 laboratories:
“DNA-free” laboratory – This laboratory is mainly used to prepare sampling kits. It must be equipped with an access hatch and be maintained in positive pressure in order to avoid external contaminants.
“Rare DNA” laboratory – DNA extractions from water samples, sediments, soil or faeces are performed in this laboratory. This room should also be equipped with an access hatch and maintained in positive pressure.
“Classical DNA” laboratory – This room is used to perform DNA extractions from tissue samples (for the construction of genetic reference databases) and to include positive controls before the amplification step.
“Amplified DNA” laboratory – The DNA amplifications are performed in this laboratory. It is crucial that it is maintained in negative pressure or isolated in a separate building to prevent contamination of other labs from DNA present at high concentration in this room.
The SPYGEN laboratories
In order to guarantee the quality of our services, SPYGEN owns an analysis platform of 200 m², specifically designed to perform eDNA analyses. It consists of 5 laboratory rooms: