00:02
So contamination is a huge issue for pcr reaction because pcr amplifies trace amount of dna sample.
00:11
Even there's a tiny bit of contamination in the tube, it will cause issues or more obvious issues when the samples is being amplified exponentially.
00:22
The source of contamination, i listed the major source of them underneath.
00:28
So one big source of contamination is the sample collection.
00:32
For example, when the q -tip swiped the crime scene, more than one person's sample is being collected at the same time.
00:38
So two different persons ' blood sample is being collected and put in the same tube.
00:43
That could be a main source of contamination.
00:45
Other things, including the cross -contamination of sample during transportation.
00:50
So during the transportation to a lab, maybe one tube leaks and got into the other tube.
00:58
In the same box.
01:00
So that could be another source of contamination...