Masha Gessen was faced with a terrifying choice: cut off her breasts, and possibly save herself from cancer, or use them to feed her child. It was late at night when I walked back to my empty dorm room at the conference. Shivering, I stood on the narrow bed, quickly ...
Getting an accurate genome sequence requires that you collect the data at least twice argue Robasky, Lewis, and Church in their recent opinion piece in Nat. Rev. Genetics [1]. The DNA sequencing world kicked off 2014 with an audacious start. Andrew Pollack ran an article in the New York Times ...
I made this video (below the fold) to illustrate the steps involved in making a phylogenetic tree. The basic steps are to: Build a data set Align the sequences Make a tree In the class that I'm teaching, we're making these trees in order to compare sequences from our metagenomics ...
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 ...
One of the holy grails of modern medicine is the development of a vaccine against HIV, the virus that causes AIDs. An obstacle to attaining this goal has been the difficulty in stimulating the immune system to make it produce the right kinds of antibodies. A recent finding in Science ...
August is the time when gardens look their best. Fruit becomes showy, flowers abound, and plants are large and plentiful. Mendel's Garden #4, currently blooming at The Inoculated Mind, is no exception. Evolgen pointed this out, so I had to go take a look. I enjoyed this trip through the ...
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 ...
What do you do after you've used DNA sequencing to identify the bacteria, viruses, or other organisms in the environment? What's the next step? This four part video series covers those next steps. In this part, we learn that a surprisingly large portion of bioinformatics, or any type of informatics ...
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 ...
`When I make a word do a lot of work like that,' said Humpty Dumpty, `I always pay it extra.' -Through the Looking Glass by Lewis Carroll In biology, we often ask our words do a lot of work. In what other field would we write direction like this "Transfer ...
No more delays! BLAST away! Time to blast. Let's see what it means for sequences to be similar. First, we'll plan our experiment. When I think about digital biology experiments, I organize the steps in the following way: A. Defining the question B. Making the data sets C. Analyzing the ...
A few weeks back, we published a review about the development and role of the human reference genome. A key point of the reference genome is that it is not a single sequence. Instead it is an assembly of consensus sequences that are designed to deal with variation in the ...
'Tis the holiday season and, according to ancient lore, the time when miraculous events are most likely to take place. One of those well-known and miraculous events of ancient days was the birth of a son to a young girl, who, although she was married ( Okay, I'm not sure ...
This afternoon, I was working on educational activities and suddenly realized that the H1N1 strain that caused the California outbreak might be the same strain that caused an outbreak in 2007 at an Ohio country fair. UPDATE: I'm not so certain anymore that the strains are the same. I'm doing ...
Here's a fun puzzler for you to figure out. The blast graph is here: The table with scores is here, click the table to see a bigger image: And here is the puzzling part: Why is the total score so high? If you want to repeat this for yourself, go ...
Like biology, all bioinformatics is based on the idea that living things shared a common ancestor. I have posted, and will post other articles that test that notion, but for the moment, we're going to use that idea as a starting point in today's quest. If we agree that we ...
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 ...
As many of you know, I'm a big fan of do-it-yourself biology. Digital biology, the field that I write about, is particularly well-suited to this kind of fun and exploration. Last week, I wrote some instructions for making a phylogenetic tree from mitochondrial genomes. This week, we'll continue our analysis ...
Last week, we decided to compare a human mitochondrial DNA sequence with the mitochondrial sequences of our cousins, the apes, and find out how similar these sequences really are. The answer is: really, really, similar. And you can see that, in the BLAST graph, below the fold. A quick glance ...
During these past couple of weeks, we've been comparing mitochondrial DNA sequences from humans and great apes, in order to see how similar the sequences are. Last week, I got distracted by finding a copy of a human mitochondrial genome, that somehow got out of a mitochondria, and got stuck ...
The past few Fridays, we've been comparing human mitochondrial DNA with the mitochondrial DNA of different apes. We started doing this here, where you can find directions for getting started. And, we've found some interesting things. In this installment, we found that humans have practically an entire mitochondrial genome stuck ...
We've had a good time in the past few last weeks, identifying unknown sequences and learning our way around a GenBank nucleotide record. To some people, it seems that this is all there is to doing digital biology. They would, of course, be wrong. We can do much, much more ...
If we compare sections 1, 2, and 3, we see that section 2 matches very well in a number of different samples, and that there are differences between the sequences in sections 1 and 3. We also learn something about the people who did the experiment. At first it appears ...
During the past few Fridays (or least here and here), we've been looking at a paper that was published from China with some Β-lactamase sequences that were supposedly from Streptococcus pneumoniae. The amazing thing about these particular sequences is that Β-lactamase has never been seen in S. pneumoniae before, making ...
If you look below the fold, you can see two molecules locked in a tight embrace. These molecules or their closely related cousins can be found in any cell because their ability to evolve is slowed by their need to interact with each other in the right way. In an ...
The American Society for Human Genetics is sponsoring the second annual DNA Day Essay contest. If you are a high school teacher here's your chance to combine an interesting assignment along with a contest. This year's essay questions are: If you could be a human genetics researcher, what would you ...
What happens when high school students clone and sequence genomic DNA? Background 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 ...
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 ...
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 ...
Sometimes I think the field of biology suffers from collective amnesia. Like the girl in the movie "50 first dates," we discover things over and over and every time we find something, we forget that it's ever been found before. This is especially true if a phenomenon has been discovered ...
One of my hobbies lately has been to get either RNA seq or microarray data from GEO and do quick analyses. Not only is this fun, I can find good examples to use for teaching biology. One of these fun examples comes from some Arabidopsis data. In this experiment, some ...
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 ...
I was pretty impressed to find the swine flu genome sequences, from the cases in California and Texas, already for viewing at the NCBI. You can get them and work them, too. It's pretty easy. Tomorrow, we'll align sequences and make trees. Activity 3: Getting the swine flu sequence data ...
I'm in Berkeley right now at the annual Bio-Link Summer Fellows forum. We're getting to hear talks from people in the biotech industry, listen to enthusiastic instructors describe their biotech programs and ideas, and try out new educational materials. Yesterday, two speakers (Damon Tighe and Jason Baumohl) from the Joint ...
I'm a big of learning from data. There are many things we can learn about swine flu and other kinds of flu by using public databases. In digital biology activity 1, we learned about the kinds of creatures that can get flu. Personally, I'm a little skeptical about the blowfly ...
If you've read any of the many stories lately about Craig Venter or Jim Watson's genome, you've probably seen a "SNP" appear somewhere. You may be wondering, and rightly so: just what is a SNP? Never fear, hopefully this post will answer some of those questions. SNP stands for Single ...
RFLP is an acronym that stands for "Restriction Fragment Length Polymorphism." That's quite a mouthful and once you've said this phrase a few times, you realize why we use the initials instead. I know a Restriction Fragment Length Polymorphism sounds like something that must be impossibly complicated to understand, but ...
A long-sought goal in genetics has been to develop therapies that can use correctly functioning genes to replace genes with defects. If we had the technology to predictably modify our genomes, we would have the ability to cure many diseases instead of having to place people on medications for their ...
For the past few days I've been avidly following Daniel MacArthur's tweets from the Personal Genome Conference at Cold Spring Harbor( @dgmacarthur #cshlpg). The Personal Genomics tweets aren't just interesting because of the science, they're interesting because MacArthur and others have started to take on the conventional dogma in genetic ...
Goodbye desktop, we're off to see the web. Both my students and I have been challenged this semester by the diversity of computer platforms, software versions, and unexpected bugs. Naturally, I turned to the world and my readers for help and suggestions. Some readers have suggested we could solve everything ...
I read about this in Bio-IT World and had to go check it out. It's called the Genome Projector and it has to be the coolest genome browser I've ever seen. They have 320 bacterial genomes to play with. Naturally, I chose our friend E. coli. The little red pins ...
I mean phone call. Because, if I thought he remembered me, I would call and say " thank you." Because of the time I spent in his lab, I know that cloning started long before Dolly. The first vertebrate animal was cloned over 50 years ago. And it wasn't a ...
Genome sequences from California and Texas isolates of the H1N1 swine flu are already available for exploration at the NCBI. Let's do a bit of digital biology and see what we can learn. Activity 1. What kinds of animals get the flu? For the past few years we've been worrying ...
Why is an eye, an eye and a nose, a nose? Why do different cells create different kinds of tissues when all the cells in a single organism start out with the same set of instructions (aka DNA)? Head, Shoulders, Knees, and Toes is a learning activity that helps students ...
Genetics textbooks abound with stories of European royalty and the hazards of having children after you've married one of your cousins. It struck me as an interesting parallel that the lion is such a popular symbol in so many royal coats of arms. Like the royal families of Europe, certain ...
Why should professional scientists have all the fun? Researchers have been engineering glowing cats, and selling glowing fish at pet stores. High school kids can do genetic engineering too, if they have the right equipment. And you can help them get the equipment by contributing to our DonorsChoose fund drive ...
Maybe you did it for the extra cash. Maybe you wanted to be part of the sperm cube public art project. Whatever the reason, it's possible, just possible, your sperm took on a life of it's own, once you left it. And now that a genome is no longer an ...
Students at Soldan International High School are participating in an amazing experiment and breaking ground that most science teachers fear to tread. Soldan students, along with hundreds of thousands of other people, are participating in the National Geographic's Genographic Project. Through this project, students send in cheek swabs, DNA is ...
A key concept in science is molecular scale. DNA is a fascinating molecule in this regard. While we cannot "see" DNA molecules without the aid of advanced technology, a full length DNA molecule can be very long. In human cells, other than sperm and eggs, six billion base pairs of ...
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 ...
