Here are some questions:
1. Why look at burgers and why only 22 samples and can you tell me what the 15 reference databases are? It was a student project with limited funding. Burgers are an appealing commodity consumed all over the world.
2. Was the finding from the initial data analysis that showed between 3-5% of DNA from each sample came from macaque monkeys surprising? Yes, but we are also aware that the reference databses used have limitations why peculiar findings were verified by extensive BLAST analysis – and found not to be monkey but cattle DNA.
3. I am not a WGS expert so how was this conclusion reached and it was later found to be cattle DNA? See above – BLAST analysis. Limitations of DBs.
4. Could you lengthen the Data string from the genome being examined so this does not happen? Potentially right of another seq platform was used providing longer reads.
5. Is part of the problem, lack of standardisation in reference databases/WGS equipment vendors? The problem is mainly due to DBs containing limited data or data of certain species.
6. Do we need WGS for food fraud, as we have NMR, stable isotope analysis and other tools? It’s a technology that could be used but taking into account the price and the DBs.
7. With the Bacillus cereus findings was that in enough levels to cause food poisoning? Was this finding expected/concerning? We hoped to find some pathogens – in this case Bacillus. The samples were not adequitly transported and stored why the bacteria easily could be further grown after the purchase. Its not concerning but show the power of the technology.
Dette var specifikke svar på spørgsmålene – ud over det havde vi løs snak om andre fund og technologien – de nutidig begrænsninger og fremtidig udvikling. Jeg sendte efterfølgende afhandlingen efter aftale med Frank Aarestrup.
I relation til DTU presse-meddelse: Mapping foods’ DNA can reveal fraud’