As a microbiologist who did this many times during my school years, with cheek cells, ecoli, peas....
This homemade crude method is not showing the DNA, but a mixtures of DNA, Protein, Cells membranes and other cytoplasmic organs and debris. All this
did was make a soup out of entire thing.
What you are seeing is just a hacked up cells.
Once you swabs your cheek, you need to add a lysis solution, which contains detergent like solution(cleaner detergent) also a Proteinase solution(this
one is not mentioned).... in order to separate DNA, you need to break open cells(detergent) and break open the Histones(proteins, needs proteinase to
break) that are attached to the DNA, remember, DNA is coiled up.
This is where you add salt, which causes the debris, but not DNA to clump together. Now to centrifuge and separate by density. This further separates
the liquid into debris section and DNA section. DNA is still mixed in the solution(they don't clump) so they stay on top, while the proteins and
debris sink to the bottom due to their mass and clump(if proteinase is not added, DNA will be mixed with proteins..well its not just DNA anymore.
After extraction of the solution containing the DNA strands, you add alcohol to clump the DNA together, which makes it visible.
There are other tests like gel electrophoresis, in order to see the strands. This is what is done during paternal testing and crime investigation, gel
separates them by strands size... , you conpare the evidence DNA with comparison DNA and if the band size match, well you have a match!, but this one
is more expensive because, you need to buy specific enzyme to cut DNA.
OP i cannot see the video but if it mentions proteinase solution, then you should have a DNA, but i doubt it would not be possible with out a
centrifuge and proteinase solution.
What you have is possibly DNA + Protein + Cell debris(due to no centrifuge).
edit on 2/1/2013 by luciddream because: (no reason given)