NERD RANT AHEAD
Okay, so I’m rewatching A Discovery of Witches and my nerd brain is laughing my ass off at this computer screen.
This is from Episode 5, about 27:44 minutes in. Matthew has just been in the lab, being all sciency, and compared “the actual physical data” from Diana’s DNA to that of their pre-eleventh century witch DNA.
But on one side of the computer screen he is looking at... is a picture of a Southern Blot, a way of visualizing DNA that was previously separated via a gel matrix (Which Matthew was sloppily preparing at about 26:30).
This technique is OLD. It was the first technique, I believe, developed to visualize DNA fragments, in 1975. Usually, the DNA is first fragmented with Restriction Enzymes that look for specific DNA sequences.
(This type of DNA analysis is also what was used in early Forensic DNA, most notably the OJ Simpson Trial.)
Now, Southern Blots still have it’s place in DNA labs, of course. But If you’re using a gel to visualize DNA it has mostly been replaced with more modern techniques that don’t involve radioactive isotopes.
I work with Mitochondrial DNA like our dear Professor Clairmont does (Why is a biochemist working with Mito DNA????). I spend 40 hrs a week sequencing ~ 1,200 of its ~16,569 base pairs and analyzing the data.
Below is what the most common DNA sequencing technique’s data looks like. Lots of pointy peaks in different colors. Gives you a headache after a few hours, trust me.
The newest technology (called Next Generation Sequencing even though it’s like the 4th generation of sequencing technology) produces data, that when visualized by a computer program, looks like the colorful strings of letters below.
Someone needs to update movie/show makers and tell them that DNA technology has changed in the past 30 years... Stop flashing around Southern Blots like they are the height of Genetic research!
Just go get the people who made the Mr. DNA sequence from Jurassic Park, those bastards were ahead of their time! OR GOOGLE SOMETHING!
Fun science fact or Why Scientists Shouldn’t Be Allowed to Name Things:
The Southern Blot method was developed by Edwin Southern, hence the name.
When the same basic method was applied to proteins, it was named the Eastern Blot... and then came the Western Blot, which did the same for RNA...