Biology/DNA Exhibit Storage and Shipping

Storage DNA Extracts and other items susceptible to degradation (e.g. muscle tissue), should be stored in a freezer at a temperature of at least minus 20 degrees Celsius.

Note - this should not be a frost-free freezer. The freeze/thaw cycles of frost-free freezers can cause ice crystallization which is detrimental to DNA molecules. Exception - Products of conception (fetal tissue) samples are susceptible to degradation immediately upon surgical removal. In addition, as little as a single freeze/thaw cycle may be detrimental to obtaining DNA results.

• Refrigerate and ship immediately.

• DO NOT freeze products of conception unless the sample was already frozen at the time of the seizure. If already frozen, it should be kept frozen (avoid freeze-thaw-freeze).

• It is preferable not to place in formalin/formaldehyde or any other preservative. If the sample is in formalin, formaldehyde or paraffin, it must not be frozen.

• Package on ice and send to NFLS as soon as possible using expedited transport.

Swabs, clothing and other items For other exhibits such as swabs and clothing items, they can be stored at room temperature in a dry, dark location provided that they have been thoroughly dried. Ideal temperatures are between 16-24 degrees Celsius with humidity below 60%. Moisture encourages microbial growth which will lead to degradation of the biological samples which is detrimental to obtaining DNA. If the exhibit items are suspected of being damp in any way and in order to prevent mould growth and microbial action, the items too should be placed in the freezer (again not a frost free freezer). Shipping Ideally, for exhibits that are being taken out of the freezer for shipment, it is important to get the exhibits to the laboratory as quickly as possible (same day or overnight delivery). It is recommended that items not be shipped on a Friday or just prior to a holiday to ensure prompt delivery to the laboratory. It is also important to keep exhibit material as cold as possible during shipment. Insulated containers and ice packs can be used to achieve this. Some microbes are able to survive freezing and the damp conditions will allow them to grow when not kept frozen. For exhibits that have been dried thoroughly and packaged properly, standard delivery is acceptable - no need for fast shipment or ice packs. If you are shipping from a remote location with limited mail service, Air Mail may be the best way to expedite the shipment. It is also recommended that a good drying cabinet be used, when appropriate, to ensure most items are thoroughly dried.