Ever wonder how all the new cells in your body get a copy of your DNA? Well, it’s not sent through an office memo. DNA replication is a very intricate and fascinating process you don’t want to miss. In this video, we’ll give a brief overview of DNA replication for eukaryote cells and introduce 4 key players: ligase, DNA polymerase, primase, and helicase. We’ll also talk about why DNA can either run 5’ to 3’ or 3’ to 5’ by exploring the structure of DNA.
Copy number variation and the secret of life - with Aoife McLysaght
Evolution is powered by variation: the differences in DNA sequences. One hugely important form of difference is copy number variation, where genes are duplicated or deleted from one generation to the next.
In this Ri event, Aoife McLysaght from Univeristy of Dublin explains how copy number variations gave us colour vision, a sense of smell and haemoglobin in our blood, before exploring the role they play in diseases such as cancer, autism and schizophrenia.
The event ‘Too Much of a Good Thing’ was presented at the Ri on Friday 28 March and forms part of the Ri’s all-women line up for Friday Evening Discourses in 2014 as part of a year-long celebration of women in science.
Got milk? Fact is, most people don’t — and shouldn’t — because for them, ice cream and milkshakes are basically toxic. So why can some people drink milk and survive? Turns out they’re mutants! SciShow explains.
Science Friction №27 - Create Your Own Clone
On Orphan Black, scientists are capable of creating human clones. It turns out that scientists in real life are doing this as well. Find out how to create your own clone in this episode of Science Friction.
When a man and a woman have sex, it’s very possible that they can create a baby! This is nothing new, but is it possible for a baby to have three biological parents? Laci takes a look at how this is possible, and why it could actually result in healthier babies!
Have Scientists Debunked the Myth of the Blonde Ditz?
“Researchers discover that being blond does not make people ditzy,” reads a recent NY Daily News headline. That’s not actually true, but there is evidence to suggest a correlation between lack of intelligence and being a writer for the NY Daily News.
Journalist David Harding goes on to ask, “Is the end of jokes about “blond moments?” I’m not sure, David, IS THE END?
Here’s what actually happened: molecular biologists at Stanford School of Medicine identified a single mutation in the DNA that regulates the KITLG gene that changed the color of the stickleback fish from dark to light.
Epigenetics means women have different active x-chromosomes in different cells.
When a female embryo is four days old it consists of just 100 cells. At this point the x-chromosome from Mom and the one from Dad are both active. But in order for proper development to occur, one of the x chromosomes must be switched off.
Through a tiny molecular battle within each cell, one of the x-chromosomes wins and remains active while the loser is deactivated.
This is done by wrapping the DNA tighter around proteins, modifying histone tails, and DNA methylation - molecular markers to indicate this DNA should not be read.
What’s surprising is that it’s pretty random which x chromosome wins - sometimes it’s Mom’s and sometimes it’s Dad’s. So when a female is just 100 cells big, her cells have a mix of active x-chromosomes, some from Mom and some from Dad.
Until recently cancers were seen as lifestyle and genetic diseases, brought on by exposure to carcinogens or a mutated gene. Recent studies are linking microbes to many different kinds of cancers. Participants will discuss not only how infection with specific pathogens causes cancers but also how disruptions in the human microbiome can also cause disease.
Christian Jobin, University of Florida, Gainesville
Paul Andersen explains how the frequency of recombination between linked genes can be used to determine the relative location of genes on a chromosome. Thomas Hunt Morgan and Alfred Strutevant used the fruit fly to develop a theory of chromosomal inheritance and discover crossing over.
Technology used to fight crime and catch criminals is getting pretty advanced. A new experimental technique can take the DNA from a single strand of hair and generate a mugshot! Anthony is here to tell you how this technology works and what it could mean for the future of crime fighting.