Science Buddies: "Ask an Expert"

Hair color intrigues me because I have red hair and my siblings have brown, black, and blond hair. I would like to compare the gene sequence of my DNA to that of my siblings in order to understand hair color. I know how to get the DNA from our cheeks and I know how to compare two sequences of DNA using BLAST. I don't know the middle step(s) of reading our DNA to pull out the sequence that codes for hair color. Is this something that I would be able to do in a high school lab? If so, can you explain the process?

This is a really cool idea, but might be difficult to execute. Hair color is controlled by many genes, and it isn't even fully understood. This would make it difficult for you to sequence a specific spot of DNA to compare.

Here is a project about trait analysis in families that you might find interesting:
https://www.sciencebuddies.org/science- ... #procedure

Let us know if you have any more questions!

Thank you. I do think that is interesting. This is a science fair project for my AP Bio class, and I will ask my teacher if she considers this a "hard enough" project. Otherwise, if I chose a different trait, can I sequence a specific spot of DNA to compare?

You might be interested in studying the MC1R gene, which encodes for the MC1R protein. This G-Coupled protein function as a receptor on the surface of melanocytes, and MC1R regulates pigment (melanin) production in mammals. Hair color is determined by the balance of eumelanin and pheomelanin pigments. The former produces colors ranging from blonde to black, while the latter produces red colored pigments. r variants of the MC1R gene are associated with red hair and pale skin. For your AP Bio project, you can use BLAST to compare how your and your relatives' MC1R DNA sequences aligns with an MC1R DNA sequence from the BLAST database. You would especially want to look at the E value, because the E value indicates the likelihood similarities between DNA sequences are due to chance or to homology.

That is exactly what I'd like to do! How would I do this? We have a centrifuge to do the extraction, but how would we read the DNA?

Do you have access to any DNA sequencing technologies? Or labs that carry those technologies? You might want to contact them first.