3 ms·

Does this mean that inexpensive DNA tests you can buy online are likely to contain contaminated samples? As the person taking the sample at home hardly has stri

• dekhn 4y ago
  No, tests like that work with an abundance of DNA and so contamination is less likely. A DNA test typically works with saliva or blood which contains a ton of DNA> That DNA can then be amplified, which amplifies both the signal and the noise, but the noise is very low and can be trivially ignored after the fact. With paleogenomics, you're collecting a tiny amount of DNA, mostly degraded, from ancient samples, and so the "noise" (contamination DNA) ends up being close to or more than the signal you get from the sample. Details here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3926038/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3926038/
• jhbadger 4y ago
  The issue with paleo DNA is that the target is much lower in concentration than potential contaminants from the lab worker. etc. This wouldn't be the case in DNA tests where the concentration of the sample would be comparatively high.