My Life in DNA

       In a Genetics class I am taking this semester we were taught how to isolate our mitochondrial DNA (a circular type of DNA that we get from our mothers). We did this early on in the semester. The professors then sequenced our DNA and posted the sequence online. We were each given numbers so everyone's DNA was anonymous. We were all able to analyze our DNA using a program called Finch (Download FinchTV). This program showed peaks at bases where the DNA was clean and crisp. The more careful and the more often you isolate your DNA the better the peaks come out. We were able to copy a portion of our DNA sequence into an online database to be compared with thousands of other individuals. We used BLAST through the NCBI database. The picture below is my DNA(the top sequence) and another human's DNA(the bottom sequence). We have a 99% match! That's pretty incredible especially since I have no clue who this person may be.

 

       I was also able to compare my DNA to the DNA of others in the class by using ClustalW, a multiple sequence alignment program. My brother just so happens to be in this class also, so I decided to look at our DNA together. This is what came up:

 

 

      The asterisk under the letters signifies a match in the bases. My brother and I have a 93% match, which is actually pretty different. The reason we aren't closer than that is because we both have deletions in our DNA. I have a deletion at the beginning of this sequence and he has one a few bases in.

       The DNA that we isolated and viewed is non-coding DNA so having a deletion in this section of the DNA isn't that big of a deal. Luckily!

       Interestingly enough, I compared my DNA to a friend of mine who is also in the class and we had a 94% match. I am more closely related to this friend than I am to my own brother! It's wierd to think that you could be more closely related to someone you have never met than your own family. But mutations can change one's DNA in many ways. Since both my brother and I have a mutation in this portion of our DNA it makes sense that we would have a 7% difference.