Last year I wrote about an experiment where I compared a human mitochondrial DNA sequence to primate sequences in the GenBank. Since I wanted to know about the differences between humans, gorillas, and chimps, I used the Entrez query 'Great Apes' to limit my search to a set of sequences in the PopSet database that contained gorillas, bonobos, chimps, and human DNA.
A week ago, I tried to repeat this experiment and...
Reposted from Halloween 2006.
Since Ben shared his family's taxonomy of candy types, and it's Friday, after all, I thought I'd share some of things that we do with candy around our house and describe some fun things that you can do with candy at home. ... Read more
Metagenomics is a field where people interrogate the living world by isolating and sequencing nucleic acids. Since all living things have DNA, and viruses have either DNA or RNA, we can identify who's around by looking at bits of their genome.
Researchers are using this approach to find the culprit that's killing the honeybees. We're also trying to find out who else shares our bodies, and lives in our skin, in our stomachs, and other places where the sun doesn't shine. Craig Venter used ... Read more
The simple fact is this: some DNA sequences are more believable than others.
The problem is, that many students and researchers never see any of the metrics that we use for evaluating whether a sequence is "good" and whether a sequence is "bad."
All they see are the base calls and sequences: ATAGATAGACGAGTAG, without any supporting information to help them evaluate if the sequence is correct. If DNA sequencing and personalized genetic testing are to become commonplace, the practice of ignoring data quality is (in my opinion) simply unacceptable.
So, for awhile anyway, I'm ... Read more
We have lots of DNA samples from bacteria that were isolated from dirt. Now it's time to our own metagenomics project and figure out what they are. Our class project is on a much smaller scale than the honeybee metagenomics project that I wrote about yesterday, but we're using many of the same principles.
The general process is this:
1. We sort the chromatogram data to identify good data and separate it from bad data. Informatics can help you determine if data is
Would you like to have some fun playing with chromatograms and helping our class identify bacteria in the dirt?
This quarter, my bioinformatics class, at Shoreline Community College, will be working with chromatograms that were obtained by students at Johns Hopkins University, and graciously made available by Dr. Rebecca Pearlman. (See see "Sequencing the campus at the Johns Hopkins University" for more background.)
We are going to do a bit of metagenomics by using FinchTV and ... Read more
Welcome Bio256 students!
This quarter, we're going to do some very cool things. We are going to use bioinformatics resources and tools to investigate some biological questions. My goal, is for you to remember that these resources exist and hopefully, be able to use them when you're out working in the biotech world. I don't believe that bioinformatics is a subject that you can really grasp without getting your fingers dirty. So, this course will include a lot of hands-on work.
My friend and collaborator at Johns Hopkins University has given me data sets from the past three years and ... Read more
Two protein structures from an avian influenza virus are shown below. One form of the protein makes influenza virus resistant to Oseltamivir (Tamiflu®)
Don't worry, these proteins aren't from H5N1, but they do come from a related influenza virus that also infects birds.
One protein structure is from a strain that is sensitive to an anti-viral drug called "Tamiflu®". The other structure is from the same virus, except there's a slight difference. A single base change in the viral RNA changed the codon that tells the translation ... Read more
I began this series last week with a question about a DNA sequence that was published and reported to be one the first beta-lactamases to be found in Streptococcus pneumoniae. Mike has a great post about one of problems with this paper.
I think the data themselves are awfully suspicious.
So, last week I suggested that you, dear readers, go and find out why. I gave you a ... Read more
Charles Darwin was so fascinated by beetles he paid people to help him build his collection. The Coleopterists Society and the Smithsonian Institute want to help kids explore the wonders of beetles, too.
They're providing grants for kids, in grades 7-12 to work on beetle biology.
Applications are due by November 15, 2007.
... 