Me PCR Noob, plz halp :c

Hi, I am new both in biohacking and this forum.

I don’t even know if this is the right place to ask stuff like this, but I am struggling to set up a workshop an Polimerase Chain Reaction and I need some advice.

The internet is giving me plenty of information about region-specific primers, but I am looking to replicate an entire human DNA-Strand (extracted from mouth cells).

Do I even need a common primer or another thing entirely?

Hej! Welcome!!
Quite an ambitious project.

First, i’d suggest you to look into the maximum replication length for the polymerase that you want to use. If you need good quality, I would not recommend to amplify much more than 1000 bp at a time. This would mean that you need around 12 Million Primers and would end up with 6 Million Fragments that you then need to assemble into the 23 chromosomes… thats a looooot of work.

Our cells do this all the time. It’s called replication.

What do you want do do with the DNA?
Maybe you can just make more extract?

Hi julian,

thanks for the complimant :upside_down_face: .

The goal of the workshop is to introduce the participants to the process of making a
genetic fingerprint, the way it is typically done in forensics.
For that, I want to multiply the DNA from a small saliva-sample, so it shows clear bands after Gelelektrophoresis.

BTW i’m german sorry for the fuzzy english.

It is possible that the technique you are thinking of is done in a different way to how you think it works.

Genetic fingerprinting is done with DNA restriction enzymes, and polymerases, but not DNA primers.

It is described in,applied%20along%20the%20gel%20plate.

The tricky technology is a pulsed field agarose gel setup.

Big DNA fragments are hard to get through the agarose.

The pulses push it harder.

Others will know better than me.


Hi Brian,

I see, but before doing the Gelelektrophoresis bit, I wanna multiply the DNA sample for a better result. Do you know how this is done?

The genetic fingerprint can surely be done in a workshop context. I used to do it long time ago with undergraduate students.

For this you want to do a PCR on VNTRs (“variable number of tandem repeats”). They consist of repeats from a specific sequence of the DNA that are inherited and their number varies from person to person. You just need the right primers (cant help you with that though) and a simple electrophoresis. No pulsed field necessary.

Where are you based and in which context do you plan to do the workshop?

Sorry, the method I mentioned was an oldschool technique.

Thanks, now I only have to find out were those VNTRs are.

I am hanging out in Germany, specifically the “Maker Space Bonn”, which isn’t necessarily the right place for DNA-Stuff, but no place in Germany is great for that.

I want to do this workshop just out of personal interests, because I want Germany to be more open towards this technology and also quite frankly because I need money :sweat_smile: .

I’m not a student. I think they call the thing I am a “Citizen Scientist”.

There is a Bio Rad Kit for that. It is expensive, but comes with everything you need. It also contains artificial human DNA samples because to take and analyse human samples on your own is kind of a legal grey area in Germany (as far as I know. Please correct me if I’m wrong).

We successfully used this kit in workshops at our makerspace.