Question: How do you understand dna?

Matthew Lee answered on 16 Jun 2017:

We can understand DNA in a number of different ways. One way is through sequencing, this is where we read the entire genome of a person and say what is in their genome, and whether they have specific genes for brown eyes or blue eyes for example. This is quite a complex procedure but we use machines to do this for us and then the machine gives us a really really big file of data and we use special computer programmes to go through the data and tell us what the DNA says.

Another way is to look at the DNA through another mechanism like through the products of the DNA. For example say we are interested in gene ABC, we know what gene ABC does it gives people cancer and it does that because it makes a protein called 123. So what we can do is we can look for protein 123 in cells and if it is there we can infer that gene ABC is also there as you only get protein 123 if gene ABC is present. If protein 123 isn’t there this doesnt mean gene ABC isn’t there tho, it could just mean it isn’t working and so it might have mutated. To find out if it has mutated we could sequence it as above and see what has changed.

Another technique which is quite cool looks at how proteins interact with DNA. This is called chromatin immunoprecipitation or Chip. What happens is, is that we activate the piece of DNA or protein and then wait for them to interact, then we do a special technique that freezes them together (but not the cold kind of freeze, more like gluing but without glue) then we chop up all the DNA into small pieces and destroy it. This means that all that is left is the bit of protein that is attached to the DNA. then we unfreeze the protein and DNA, wash away the protein and then look at what DNA is left. This will then tell us what bit of DNA that protein is interacting with. It’s really cool and i really want to learn to do it in the lab!