Large amounts of silica gel-preserved material are currently scattered throughout the department; DNA samples have been accumulating more and more rapidly in recent years. The molecular collections section is a very new one, charged with bringing all this material together in optimal storage conditions.
The material will be held in the Darwin Centre. Consolidation of the collections will begin as soon as the centre opens in September 2009.
The two types of material receive very different preparation treatments:
- Silica gel-preserved material
Small samples of fresh material are air dried and stored in sealed bags with silica gel crystals. This ensures the material remains dry and well-preserved without the use of any chemicals or treatments which might damage DNA.
- DNA samples
Pieces of silica gel-preserved specimens are finely ground using an automated grinder, or sometimes by hand using a mortar and pestle. DNA is extracted using primers and amplified if necessary. These are used for DNA sequencing. Spare material is stored and can be used for further investigations.