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From
Secretariat to Seabiscuit, it turns out that all thoroughbred race horses
were all related. They shared a single ancestor in the mid 17th century,
whose "speed gene" was a genetic aberration:
Emmeline Hill of University College Dublin led a team that analyzed DNA in 593 horses from 22 modern breeds, as well as museum specimens from 12 historically famous stallions. Modern genetics have become sophisticated enough that they could tell, with considerable precision, what the horses had in common.
"The results show that the 'speed gene' entered the thoroughbred from a single founder, which was most likely a British mare about 300 years ago when local British horse types were the pre-eminent racing horses, prior to the formal foundation of the thoroughbred racehorse," said Hill in a prepared statement.
Scientists
discovered that people who need only a few hours of sleep each night before
waking up refreshed and full of energy (no coffee required!) owe this
ability to a single gene:
The Europe-wide study saw 4,000 people from seven EU countries fill out a questionnaire assessing their sleep habits. The researchers then scanned the genomes of the volunteers and looked for variations in their genes that correlated with their answers about their sleep patterns.
They discovered that people who had two copies of one common variant of ABCC9 slept for significantly shorter periods than people with two copies of another version.
The finding, described in the journal Molecular Psychiatry, could explain why light sleepers are able to get by on just a few hours of shut-eye a night, says Toronto-based sleep expert Dr. Colin Shapiro.
"This tells us that we are programmed in some way to need a certain amount of sleep, just as some people are programmed to be taller and others are programmed to be shorter," he told CTV's Canada AM Tuesday morning.
Link - via Booster Shots
Two
mice meet in a narrow plastic tube that's not wide enough for both of them.
That sounds like the opening of a really bad science joke, but stick with
me. The punchline is downright amazing:
One of them must give way. In their earlier encounter, the first mouse exerted its dominance by forcing its rival to reverse down the tube. This time, things are different; the second mouse pulls rank and the first one backs down.
Mouse hierarchies don’t change this readily, but the second mouse has been given a boon by Fei Wang at the Chinese Academy of Science. By injecting a single gene into one part of its brain, Wang turned the subordinate animal into a dominant one.The gene that gave the mouse a burst of social mobility is GluR4. It creates part of a protein called the AMPA receptor, which allows signals to flow quickly between two neurons. By injecting extra GluR4 into a mouse’s brain, and producing more AMPA receptors, Wang strengthened the connections between its neurons. The effect is like building expressways between two cities overnight – you can have a much larger and faster flow of traffic between them. [...]
By manipulating this signalling, he could push mice up or down the social ladder. With an extra dose of GluR4, the mice gained social standing. When they confronted other mice in a cramped plastic tube, they were more likely to force their rivals to retreat, even if they had previously given way. With their new rank, they were also more likely to court female mice with high-pitched ultrasonic songs.
Here’s an interesting project. Quebecois artist Ulric Collette (shown above, with his cousin Justine) explores the facial similarity of relatives by mashing their faces together into one portrait. The Genetic Portraits series was featured in My Modern Met, who snagged an interview with Collette. There are a lot of great results–some look like a normal person (when the relatives are close in appearance) and some can be kind of crazy. Link -via Laughing Squid
Research into why Transylvanian naked neck chickens have naked necks reveals a complex balance between genes and chemicals that produce a bird’s (not just chickens) feather pattern while it is still an embryo in an egg. Once the combination was discovered, Chunyan Mou from the University of Edinburgh found that bird necks are naturally more disposed to nakedness than the rest of their bodies. This may be no benefit to poultry, but chickens are related to birds that do benefit.
Mou thinks that similar genetic tweaks have happened time and again in the evolution of birds. Many groups have lost their neck feathers independently, including vultures, the marabou stork, and large flightless birds like ostriches and emus. Naked necks allow vultures to stuff their heads into carcasses without soiling any feathers; in other cases, a naked neck probably helps its owner to keep cool in hot climates.
Whatever the benefit, it seems that it’s particularly easy for birds to evolve a naked neck, rather than another part of their body. After all, Mou found that the necks of embryonic ducks, turkeys, quails and guinea fowl all have much higher levels of retinoic acid than the rest of the body. This pattern would normally be innocuous, completely hidden from natural selection. But it allows BMP-boosting mutations to denude the neck in one fell swoop, while keeping the rest of the body covered in feathers. As Mou writes, “An underlying map within the skin provides a one-step route to a bare neck.”
The post goes into detail about how the genes initiate the production of chemical activators and inhibitors, and ends with a parable from Alan Turing that explains the concept in layman’s terms. Link
(Image credit: Demontux)
Why do siblings – despite having much of the same genes and upbringing – grow up to be have such different personalities?
NPR’s Alix Spiegel explores:
Then in the 1980s, a researcher named Robert Plomin published a surprising paper in which he reviewed the three main ways psychologists had studied siblings: physical characteristics, intelligence and personality. According to Plomin, in two of these areas, siblings were really quite similar.
Physically, siblings tended to differ somewhat, but they were a lot more similar on average when compared to children picked at random from the population. That’s also true of cognitive abilities.
"The surprise," says Plomin, "is when you turn to personality."
Turns out that on tests that measure personality — stuff like how extroverted you are, how conscientious — siblings are practically like strangers.
"Children in the same family are more similar than children taken at random from the population," Plomin says, "but not much more."
In fact, in terms of personality, we are similar to our siblings only about 20 percent of the time. Given the fact that we share genes, homes, routines and parents, this makes no sense. What makes children in the same family so different?
Link – via Cliff Pickover’s Reality Carnival
A genetic study of Icelandic natives found a genetic variation in 80 people similar to a variation found mostly in Native Americans. The genetic code was traced back to four women who lived around 1700. But the history of Iceland leads experts to believe the gene must’ve entered the population hundreds of years earlier. The simplest answer so far that fits the facts is that some Viking brought back a Native American wife from North America, who then bore the first Viking-American child in Iceland.
“We know that Vikings sailed to the Americas,” said Agnar Helgason of deCODE Genetics and the University of Iceland, who co-wrote the study with his student Sigrídur Ebenesersdóttir and colleagues. “So all you have to do is assume … that they met some people and ended up taking at least one female back with them.
“Although it’s maybe interesting and surprising, it’s not all that incredible,” Helgason added. “The alternative explanations to me are less likely”—for example the idea that the genetic trait might exist independently, undiscovered, in a few Europeans.
Link -Thanks, Marilyn!
(Image credit: Robert Harding Picture Library, Alamy)
Researchers at the University of Bonn have found that people with a certain gene are more likely to be altruistic. The researchers took a genetic sample from study participants, and then asked them to participate in a quiz on memory retention. For this, participants were given five Euros, and invited to donate that amount to a charity. Prof. Martin Reuter described what happened:
“Students with the COMT-Val gene donated twice as much money on average as did fellow students with the COMT-Met variant,” explains Reuter. This is the first time that researchers have been able to establish a connection between a particular gene and altruistic deeds. However, it was already known from studies on twins that altruistic behavior is also partly influenced by our genes.
Link via Hit & Run | Photo by Flickr user meddygarnet used under Creative Commons license
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Poet Christian Bök plans to alter the DNA of a particular species of bacteria so that it reflects an encoded version of his poetry:
Canadian poet Christian Bök wants his work to live on after he’s gone. Like, billions of years after. He’s going to encode it directly into the DNA of the hardy bacteria Deinococcus radiodurans. If it works, his poem could outlast the human race. But it’s a tricky procedure, and Bök is doing what he can to make it even trickier. He wants to inject the DNA with a string of nucleotides that form a comprehensible poem, and he also wants the protein that the cell produces in response to form a second comprehensible poem.[...]
Bök will create a code that links letters of the alphabet with genetic nucleotides (adenine, cytosine, guanine, and thymine, aka ACGT). Each triplet of nucleotides will correspond to a letter so that, say, ACT represents the letter a, AGT represents the letter b, and so on.
Link via Marginal Revolution | Image: US Department of Energy
Okay, I made up the last bit. But these fish have been altered to grow far more muscular than normal trout:
The bodybuilder stature of the trout comes from turning off myostatin, a protein that normally slows muscle growth. Researchers had known of a natural myostatin mutation that allowed for 20 to 25 percent more muscle growth in Belgian blue cattle, but did not know if the same would apply to the different mechanism of muscle growth in fish.
Terry Bradley, a fisheries and aquaculture expert at the University of Rhode Island, worked with a group of grad students for 500 hours to inject 20,000 rainbow trout eggs with different DNA snippets designed to block myostatin.
About 300 eggs ended up carrying the gene for more muscle growth, and eventually produced fish that mostly have the six-pack ab appearance — even though the fish don’t have standard abdominal muscles. A big dorsal hump adds the appearance of muscular shoulders.
Photos at the link.
Scientists at the International Cancer Genome Consortium assert that they have genetically decoded lung and skin cancer. This will allow the development of drugs that specifically attack cancer at the genetic level because it will be possible to determine precisely which mutations cause certain cancers:
The scientists found the DNA code for a skin cancer called melanoma contained more than 30,000 errors almost entirely caused by too much sun exposure.
The lung cancer DNA code had more than 23,000 errors largely triggered by cigarette smoke exposure.
From this, the experts estimate a typical smoker acquires one new mutation for every 15 cigarettes they smoke.
Link via Popular Science | Image: US Department of Health and Human Services
Medical researchers at the European Molecular Biology Laboratory in Heidelberg, Germany, altered a single gene in female mice. The mice did not change anatomically, but their ovaries began producing testosterone:
The study was carried out on mice but the implications are relevant to humans, the scientists said. By switching off a gene called FoxL2, which exists in all mammals, the ovary cells of adult female mice developed spontaneously into the fully developed, testosterone-producing cells found in male testes, although they could not produce sperm.
“We take it for granted that we maintain the sex we are born with, including whether we have testes or ovaries,” said Robin Lovell-Badge, from the Medical Research Council’s National Institute of Medical Research in north London, who was part of the international team led by the European Molecular Biology Laboratory in Heidelberg.
The scientists noted that their research contradicts the claim that female is the default gender among embryos without a male sex-determining gene.
Link via Popular Science | Photo: US Department of Energy
National Geographic video link.
Last year Neatorama offered a link to a Telegraph article about a remote Brazilian village with, in Miss Cellania’s words, a “bazillion Brazilian” twins. Now Candido Godol will be the subject of an upcoming documentary in a National Geographic’s Explorer program.
The statistics are jaw-dropping: 44 pairs of twins in 80 families in a 1.5-square-mile area – a rate 1000% above the global average. Some scientists attribute this to a “founder effect” since many of these Brazilians are descendants of German immigrants who clustered in this remote outback area. Others wonder about environmental contamination or simple chance. The National Geographic program will apparently focus on the more tabloid-worthy “Joseph Mengele-was-here” hypothesis.
Via Reddit, where there is a discussion thread.
Why can humans talk and chimpanzees can’t? Scientists at UCLA and Emory University suspect that it comes down to a single gene designated FOXP2. There is only a slight variation in this gene between humans and chimps, as Elaine Schmidt writes in UCLA Newsroom:
“Earlier research suggests that the amino-acid composition of human FOXP2 changed rapidly around the same time that language emerged in modern humans,” said Dr. Daniel Geschwind, Gordon and Virginia MacDonald Distinguished Chair in Human Genetics at the David Geffen School of Medicine at UCLA. “Ours is the first study to examine the effect of these amino-acid substitutions in FOXP2 in human cells[...]“We found that a significant number of the newly identified targets are expressed differently in human and chimpanzee brains,” Geschwind said. “This suggests that FOXP2 drives these genes to behave differently in the two species.”
The research demonstrates that mutations believed to be important to FOXP2′s evolution in humans change how the gene functions, resulting in different gene targets being switched on or off in human and chimp brains.
Link via io9 | Image: US Department of Energy
There has never been a documented case of cancer found in a Naked Mole Rat, which is unusual as they can live to be 30 years old. Now biologists at the Unversity of Rochester believe they have found the reason.
The findings, presented in today’s issue of the Proceedings of the National Academy of Sciences, show that the mole rat’s cells express a gene called p16 that makes the cells “claustrophobic,” stopping the cells’ proliferation when too many of them crowd together, cutting off runaway growth before it can start. The effect of p16 is so pronounced that when researchers mutated the cells to induce a tumor, the cells’ growth barely changed, whereas regular mouse cells became fully cancerous.
“We think we’ve found the reason these mole rats don’t get cancer, and it’s a bit of a surprise,” say Vera Gorbunova and Andrei Seluanov, professors of biology at the University of Rochester and lead investigators on the discovery. “It’s very early to speculate about the implications, but if the effect of p16 can be simulated in humans we might have a way to halt cancer before it starts.”
Further research might reveal whether the findings will be applicable to humans. Link -via reddit
That’s the question that Jeremy Hsu asks, given innovations in genetic engineering:
In 2006, researchers found six Pakistani children who felt no pain due to an inactivated gene, and who constantly had bruises and cuts. One fell into the habit of putting knives through his hand and walking barefoot on coals, before his untimely death.
Still, scientists already know that humans can intellectually dissociate the sensation of pain from how much it bothers them. Lab experiments with mice have also suggested a way to disconnect that pain sensation without totally leaving animals vulnerable to a world of hurt.
Due the concern among some meat-eaters that the animals that provide their food suffer physical pain while being raised and slaughtered, Hsu wonders if geneticists may be able to create animals that cannot feel pain. Would it be ethical to do so? What do you think?
Image: Mitch Romanowski Design
Frustrated with those around office who brag about how early they got up? It appears that genetics plays a role in one’s sleep habits … and that the tendency of getting up early is caused by a mutation:
In 2001, geneticist Ying-Hui Fu and colleagues identified a mutation in a gene called Per2 that appeared to cause familial advanced sleep-phase syndrome (FASPS).
In 2005, they uncovered another mutation associated with FASPS. And now they say they have found the first genetic mutation in humans that appears to affect sleep duration rather than sleep timing. The mutation lies in DEC2, a gene that codes for a protein that helps turn off expression of other genes, including some that control circadian rhythm, the internal clock that regulates a person’s sleep-wake cycle.
The findings, says Fu, could lead to better treatments for sleep disorders.
From the Upcoming 
ueue, submitted by OddNumber.
A laboratory at Nucleix, a life-sciences company, was able to manufacture DNA that would be accurate enough to pass forensic scrutiny:
“You can just engineer a crime scene,” Nucleix founder Dan Frumkin told The New York Times. “The current forensic procedure fails to distinguish between such samples of blood, saliva, and touched surfaces with artificial DNA, and corresponding samples with in vivo generated (natural) DNA,” Frumkin and co-authors wrote in a recent Forensic Science International: Genetics study that announced the technological achievement.
Fortunately, the company offers a solution: one particular methyl group appears in naturally-occuring DNA, but not in Nucleix’s product.
Chimps may be portrayed as mischieviously fun but largely harmless by Hollywood, but the truth is anything but. In the wild, chimpanzees are killers that engage in years-long war against one another, and their behavior may explain man’s propensity for violence:
It was a four-year "war" witnessed by Dr Jane Goodall, and Dr Muller’s PhD supervisor, Richard Wrangham, a professor of primatology from Harvard University, Boston, that put an end to our cosy ideas.
In the Seventies, Prof Wrangham and Dr Goodall watched a group of chimpanzees split into two factions. One group killed every male and some of the females in the other group. The victims had recently been their companions.
Although Dr Goodall was the first to suggest it, Prof Wrangham went on to develop a theory that would explain human violence based on the aggression he had witnessed. As he points out, we are hardly a peaceful species. In Britain, men are 24 times more likely to kill or assault another person, and 263 times more likely to commit a sexual offence than a woman.
Prof Wrangham’s theory is called the Demonic Male Hypothesis. He argues that human males and chimps share a tendency to be aggressive with our closest common ancestor. Chimpanzees and humans have many attributes in common: we share approximately 98.5 per cent of our DNA, we both hunt and males show a strong desire to form alliances against other males while jockeying for status. Male chimpanzees are hostile towards other groups of chimps; you don’t even have to go to Arsenal to know that men are not dissimilar.
At one point in time in my graduate studies, I stopped being surprised at weird biological discoveries because, as one of my college professors said, when it comes to science, "there’s an exception to every rule, including this one" (think about it for a minute).
But this discovery by Morris Schweitzer and colleagues at McGill University and Montreal’s Jewish General Hospital revealed something that is mind boggling: your DNA may not be the same in different cells in your body:
Research by a group of Montreal scientists calls into question one of the most basic assumptions of human genetics: that when it comes to DNA, every cell in the body is essentially identical to every other cell.
Except for cancer, samples of diseased tissue are difficult or even impossible to take from living patients. Thus, the vast majority of genetic samples used in large-scale studies come in the form of blood. However, if it turns out that blood and tissue cells do not match genetically, these ambitious and expensive genome-wide association studies may prove to have been essentially flawed from the outset.
Researchers from the Universite de la Mediterranee-CNRS-EFS in France analyzed the DNA of Neanderthal fossils and found that the species might actually be composed of several "races":
We tend to think of Neanderthals as one species of cavemen-like creatures, but now scientists say there were actually at least three different subgroups of Neanderthals.
Using computer simulations to analyze DNA sequence fragments from 12 Neanderthal fossils, researchers found that the species can be separated into three, or maybe four, distinct genetic groups.
The evidence points to a subgroup of Neanderthals in Western Europe, another in Southern Europe near the Mediterranean, a third in Eastern Europe and the Middle East, and possibly a fourth in Western Asia. These groups have been postulated before, but this is the first study analyzing DNA data to look for genetic variations differentiating the subgroups.
(Image: NASA/JPL-Caltech)
In his art series Family Tree, photographer Bobby Neel Adams take portraits of family members (father/son, mother/daughter and so on) tear them down the middle and gluing them back together (no photoshop manipulation is involved).
The result reveals a fascinating "visual DNA" or facial similarities between the two generations of people.
Link – via andrewsullivan
From the Upcoming ueue, submitted by Minnesotastan.
Five-year-old Beatrice Rienhoff suffers from a rare genetic disorder that leaves her with very little muscle mass and a range of medical problems. Doctors don’t know exactly what’s wrong, nor how to help her.
Families facing this kind of medical uncertainty are often paralyzed by their distress. But rather than give in to his anguish, Hugh Rienhoff made an extraordinary decision: He would dig into Beatrice’s genetic code and find the answer himself. A biotechnology consultant by day, Rienhoff has been an avid student of clinical genetics since he earned his medical degree nearly 30 years ago. Now he has used this expertise to transform his Bay Area home into a makeshift genetics lab. Surrounded by his children’s artwork and bookshelves loaded with his wife’s political literature, Rienhoff set about sequencing a number of Beatrice’s genes, preparing samples using secondhand equipment and turning to public databases to interpret the results. On the desk in his attic workspace are a pair of white binders stuffed with charts detailing 20,000 of Beatrice’s base pairs; the data for nearly 1 billion can be accessed from a nearby PC. Whenever he has a spare moment, Rienhoff sequesters himself in this cluttered, carpeted room and sifts through his daughter’s DNA, one nucleotide at a time. He is hunting for the single genetic quirk responsible for Beatrice’s woes—an adenine in place of a guanine, perhaps, or an extra cytosine in a key location. If he can find the culprit, he figures, maybe he can find a treatment, too.
Reinhoff’s research hasn’t cracked the mystery yet, but he has found a treatment that helps his daughter somewhat. Along the way, he also became an advocate for other parents who are looking for answers to their children’s baffling conditions. Link
(image credit: Ye Rin Mok)
"It may be that natural selection is acting on not just things like whether or not we can resist the common cold, but also who it is that we are going to come into contact with," Fowler said in a statement.
Link - via clusterflock
From the Upcoming Queue, submitted by 
