Diseases in the DNA

Learn how several commonly known neurological diseases (PolyQ diseases) are caused by the same mistake in different parts of DNA. Nucleotides are the building blocks of DNA -- three of them code for different amino acids, which turn into the proteins that make up our body. DNA is in every one of our cells.  PolyQ disorders, like Huntington’s Disease happen when there are too many CAG’s, which code for glutamine, repeated in the wrong place. The amount of extra insertions often determines how debilitating the disease will be.

In this activity, you will establish the flow from chromosome, to DNA, to gene as a section of DNA, and finally to nucleotides that are the building blocks of DNA.  Introduce the idea that there is a specific triplet of building blocks (nucleotides) that becomes toxic if it is repeated over and over again and define Poly as this repetition.  Think critically about how the amount of the building blocks scale with the severity in the disease (through the activity).