Science Buddies: "Ask an Expert"

Hello,

I'm trying to do a project idea that is posted on this website, it's called From Genes to Genetic Diseases: What Kinds of Mutations Matter ?

(link: https://www.sciencebuddies.org/science- ... ml#summary)

I'm doing my project on Sickle-cell diseases. I'm trying to examine different pathogenic and benign variations of mutations in the gene. The main question in this project is why some gene mutations cause genetic diseases, but others do not.

I need help answering this question. I am comparing different effects and results of mutations, but I am failing to explain the significance of some of these mutations.

Thanks.

Hi there,

I can give you some general answers. Some mutations in the genetic code fail to cause changes in the amino acid sequence, due to more than one sequence of genetic code (codon) specifying the same amino acid. Another reason a mutation may not have a large effect is because it results in a so-called "conservative mutation". This means the amino acid changes but the new (mutated) amino acid is chemically similar to the original and thus the properties of the protein do not change. Is is also possible that a mutation to an amino acid simply occurs in a part of the protein that is not very sensitive to small changes in the amino acid sequence.

On the other hand, some mutations result in functional changes to the protein, which can, if severe enough, result in some sort of dysfunction identifiable as a disease condition. There is some more information at the links below. Let me know if this helps.

http://ghr.nlm.nih.gov/handbook/mutatio ... s?show=all

https://en.wikipedia.org/wiki/Mutation# ... n_function

Cheers,
Colin

Thank you so much.

Ali