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This is a subproject of the Project Biolab. The goal is to demonstrate the Polymerase Chain Reaction (PCR) technology (for general information see Wikipedia) in Brmlab and to develop it further for routine, reliable and practical use.
With a set of species specific primers it is possible to use PCR to identify the species of origin of meat and meaty foods (we have to investigate which types of food processing are compatible with the method). This might be (we have to try) a reasonably easy task suitable for the first practical PCR experiment. A pair of primers is needed for each kind of meat we want to identify. The primers should be based on the mitochondrial DNA, allowing for easier DNA isolation (thousands copies per cell, much better than just two copies per cell).
For example Matsunaga1) uses the following set for identification of cattle, pig, sheep, goat, horse, and chicken. The set is designed for multiplex PCR testing for all species in one reaction, distinguishing species by the length of the PCR product (157-439 bp):
Ilhak and Arslan2) use the following pairs for identification of cattle, pig, sheep, cat, and dog:
Other species (rat, turkey…) can be added later. Another interesting possibility could be a primer set for identification of fish and other seafood species (I suspect lot of cheating in this area). We have to find the primers in literature or design them ourselves.
See DNA barcoding on Wikipedia.
While the above method for identification of species (from meat, but also from other tissues including plants) is based on species specific primers and electrophoretic analysis of the PCR products, DNA barcoding is based on (almost) universal primers usable for many different organisms. The disadvantage is, that the PCR products have to be sequenced to identify the species (the obtained sequence is compared to a database with known species data). DIY sequencing in Brmlab is most probably not possible (or practical) in the foreseeable future, but we may try to send the products to a commercial or friendly professional laboratory for sequencing. This should not be prohibitively expensive, however preparation of a high quality PCR product suitable for sequencing will probably be a challenge by itself.
A possible alternative (with limited usability) for sequencing is the RFLP (restriction fragment length polymorphism) analysis of the PCR products. This should be possible in Brmlab with some restriction enzymes. But universal barcoding primers are useful even without the sequencing/RFLP analysis of the PCR products. With them, we can run PCR with DNA from various different sources, refining DNA isolation techniques from different materials.