• Question: How do you instruct the DNA?

    Asked by anon-220120 to Ryan on 3 Jun 2019.
    • Photo: Ryan Beveridge

      Ryan Beveridge answered on 3 Jun 2019:

      The DNA is a set of instructions, scientists have worked out the basics of how these instructions work and have figured out ways of introducing new DNA. We can make new bits of DNA that provide instructions to make things that we want in the cell.

      The easiest way to do this is with whats called a plasmid. this is a tiny circular piece of DNA that has all of the instructions the scientist is interested in, they put these in cells using a technique called transfection. Its a fancy name but just means mixing the new DNA with something that allows the cells to absorb the DNA and then adding it to the liquid that cells grow in.

      Once the DNA is inside the cell, the cell reads it like its own DNA and follows the instructions.

      For example if you have found that a person with a particular disease has a mutation in their DNA (a change in the DNA instructions that might change how a cell works), a scientist can make a copy of the mutated DNA and put it into cells that don’t have the mutation. They can then see if the cell is still behaving in the same way or look like cells from someone with the disease.

      I hope that helps, if you want more information feel free to ask another question : )

      Ryan

Comments

  • Photo: Emma

    Emma commented on :

    DNA is a list of instructions on how to make every part of your body. The instructions are stored in a code (similar to computer code stores instructions in a computer). So if your body needs to make something then it looks up the instructions in the DNA then then begins making it. There is a little machine which reads the DNA and makes a copy of the instructions, the instructions are then used to find relevant parts to build the protein (so it is similar to IKEA instructions to build something, you have to look up the item code to find the right part, and the same parts can be used to make different things, like the same screws can be used to make a wardrobe and a desk).

    For example the DNA code could be: ATG GGG GCC GGG GCC TAG
    This would be the instructions: Start reading, Glycine, Alanine, Glycine, Alanine, Stop reading.
    So you would make a very small protein of Glycine and Alanine, which is what hair is made of!

    So how do you instruct the DNA? This is a great question! We have wanted to change the instructions of the DNA for a long time, as some diseases are caused by errors in the instructions of the DNA. It’s difficult to change the instructions, because they are in every cell of the body. As Ryan mentioned, you can use plasmids, which are small circles of DNA which can go into the cell and give it new instructions, but our bodies are very good at detecting things which are foreign and removing it, so it will read the instructions for a while and then be removed. There is a new technology which can potentially be used to edit and correct the DNA, which is called CRISPR, but research is a long way off being used in people yet.