Contamination by production organism residual DNA
Plasmid DNA is frequently used in gene therapy and high purity plasmids are required. Residual DNA or proteins from the production organism (where plasmid was produced e.g. E. coli) are considered unacceptable contaminant.
Contamination by wild type virus in artificial drug virus
Viral vaccines or vectors are mostly prepared from wild type precursors, which lost their original activity. Artificial virus is less dangerous than wild type and has special characteristics. Wild type virus in a vaccine could have dangerous effect.
Viral contaminants in virus-free material
For the control of biological material it is necessary to check if the material does not contain any hazardous biological substance, such as virus.
Contamination tests on request development of method and subsequent validation can be included
The avermectins compose a class of polycyclic lactones that are used to treat parasitic worms and insect pests. They are naturally occurring compounds generated in
a fermentation process by a soil actinomycete Streptomyces avermitilis.
Correct sequence control - check if the sequence is free of mutant variant (insertion, deletion, changes), checking the sequence of interest is a good idea. Sanger sequencing method is a gold standard.