Researchers at the University of Aberdeen found low-level microbial contamination to be common in DNA-extraction kits. Contamination can affect results in some applications, such as deep sequencing of amplicons, in which microbial DNA can result in a competing signal. The researchers found when they extracted DNA from 10,000 or fewer cells of Salmonella bongori using four different commercially-available DNA-extraction kits, contaminating DNA sequences accounted for half of total sequences. The study showed the necessity of performing the appropriate controls and might result in more stringent peer review. Some manufacturers are developing cleaner extraction kits.

Source: The Scientist