One of the things that drives me crazy on occasion is nomenclature. Well, maybe not just nomenclature, it's really the continual changes in the nomenclature, and the time it takes for those changes to ripple through various databases and get reconciled with other kinds of information. And the realization that sometimes this reconciliation may never happen.
One of the projects that I've been working on during the past couple of years has involved developing educational materials that use bioinformatics tools to look at the isozymes that metabolize alcohol. As part of this ... Read more
Ancestry tests aren't just for humans anymore. We went to Petco this weekend to buy dog food and found brochures for doggy DNA testing. Now, those of you with dogs of uncertain parentage need puzzle no longer. According to Petco, their SNP test (what is a SNP?) can identify over 100 different breeds and they'll tell you which breeds are represented in your dog and whether your dog's breeding is mixed (or pure). ... Read more
This the third part of case study where we see what happens when high school students clone and sequence genomic plant DNA. In this last part, we use the results from an automated comparison program to determine if the students cloned any genes at all and, if so, which genes were cloned. (You can also read part I and part II.) Did they clone or not clone? That is the question. ... Read more
This the second part of three part case study where we see what happens when high school students clone and sequence genomic plant DNA. In this part, we do a bit of forensics to see how well their sequencing worked and to see if we can anything that could help them improve their results the next time they sequence.
How well did the sequencing work?
Anyone who sequences DNA needs to be aware of two kinds of problems that afflict their results. We can divide these into two ... Read more
What happens when high school students clone and sequence genomic DNA?
DNA sequencing is a wonderful tool for discovery and a great technique for getting students involved in molecular science. This fall, Bio-Rad will officially begin selling their DNA cloning and sequencing kit. Now, students across the country will have the tools in hand to begin their own projects cloning and sequencing plant genes.
Of course, without bioinformatics there's no way to know what's been cloned or sequenced.
This is where we come in. As part of an ... Read more
It's pretty common these days to pick up an issue of Science or Nature and see people ranting about GenBank (1). Many of the rants are triggered, at least in part, by a wide-spread misunderstanding of what GenBank is and how it works. Perhaps this can be solved through education, but I don't think that's likely. People from the NCBI can explain over and over again that some of the sequence databases in GenBank are meant to be an archival resource (2), and define the term "archive," but that's not going to help.
Confusion about database content and oversight is widespread in this ... Read more
Right or wrong, the word "dopamine" always conjures up images in my head of rats pushing levers over and over again, working desperately hard to send shots of dopamine into their tiny little rodent brains.
Dopamine, like many other neurotransmitters (chemicals that send signals in the brain), works by binding to proteins on the surface of brain cells and sending a signal ... Read more
In a recent post, I wrote about an article that I read in Science magazine on the genetics of learning.
One of things about the article that surprised me quite a bit was a mistake the authors made in placing the polymorphism in the wrong gene. I wrote about that yesterday. The other thing that surprised me was something that I found at the ... Read more
In its simplest sense, we imagine that learning occurs through a series of positive and negative rewards. Some actions lead to pleasure, others to pain, and it seems reasonable to expect that people will repeat the actions with pleasurable results and avoid those that ended in pain. Yet, we all know people who aren't deterred by the idea of punishment. We all know people who never seem to learn.
Could there be a physical reason, hidden in their genes?
In December 2007, Science published a study by Klein et. al. (1) where they asked if a specific genotype at a location ... Read more
Have you ever wondered what kinds of viruses can be found in human waste?
Mya Breitbart and team have been sequencing nucleic acids from fecal samples in order to find out. You might expect that we'd find viruses that infect humans or viruses that infect the bacteria in our gut.
I wouldn't have expected to learn the result that they found.
A large number, 60% of the viral DNA sequences were from unknown viruses. That's not a surprise. The surprise came when they looked at the RNA viruses.
Instead, the viral sequences most often came from a plant pathogen ... Read more