Genetics  

CRISPR gene drives allow scientists to change sequences of DNA and make that the resulting edited genetic trait is inherited by future generations, opening up the possibility of altering entire species forever. More than anything, the technology has led to questions: How will this new power affect humanity? What are we going to use it to change?

CRISPR genetic engineering now gives scientists the ability to change sequences of DNA and guarantee that the resulting edited genetic trait is inherited by future generations, opening up the possibility of altering entire species forever. More than anything, the technology has led to questions: How will this new power affect humanity? What are we going to use it to change?

At a recent TED talk, Jennifer Kahn questions and shares a potentially powerful application of gene drives: the development of disease-resistant mosquitoes that could knock out malaria and Zika.

Kahn talks about the work of Kevin Esvelt, the scientist behind gene drives. Gene drive systems are capable of altering the traits of wild populations and associated ecosystems.

"It's like a global search and replace, or in science terms, it makes a heterozygous trait homozygous.."

Named for the ability to "drive" themselves and nearby genes through populations of organisms over many generations, these genetic elements can spread even if they reduce the fitness of individual organisms. They do this by ensuring that they will be inherited by most - rather than only half - of offspring. Preferential inheritance can more than offset costs to the organism, permitting rapid spread through the population. CRISPR-based genome editing allows us to build gene drive systems capable of spreading different useful changes, including those that will eventually suppress or eliminate the target population.

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So, what does this mean asks Kahn? For one thing, it means we have a very powerful, but also somewhat alarming new tool. "Up until now, the fact that gene drives didn't work very well was actually kind of a relief. Normally when we mess around with an organism's genes, we make that thing less evolutionarily fit. So biologists can make all the mutant fruit flies they want without worrying about it. If some escape, natural selection just takes care of them."

Gene drives might not stay confined to what we call the target species, says Kahn. That's because of gene flow, or species interbreeding. If that happens, it's possible a gene drive could cross over, like Asian carp could infect some other kind of carp. That's not so bad if your drive just promotes a trait, like eye color. In fact, there's a decent chance that we'll see a wave of very weird fruit flies in the near future. But it could be a disaster if your drive is deigned to eliminate the species entirely.

Science journalist Kahn likes to seek out complex stories, with the goal of illuminating their nuances. She teaches in the magazine program at the UC Berkeley Graduate School of Journalism, and is a contributing writer for the New York Times Magazine; she has written features and cover stories for The New Yorker, National Geographic, Outside, Wired and many more.

Her work has appeared in the Best American Science Writing anthology series four times, most recently for the New Yorker story “A Cloud of Smoke,” a story on the complicated death of a policeman after 9/11.

SOURCE  TED

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Genomics  

There are between 20,000 and 25,000 genes in the human genome. With progress in genetic science, and an increasing understanding of these factors, new treatments for people with illnesses and disease are certain to emerge.

The well-respected geneticist Jacob Bronowski once referred to the universe as "the edge of uncertainty", and researchers are starting to discover that our conscious and unconscious actions have an effect on the universe. In short, our lives have a purpose since our thoughts are a projection of information that is held at the edge of the universe.

Before you start to highly of yourself, keep in mind that the field of genetics is also showing us that we're not necessarily at the height of creation. We only know of a handful of genes that are unique to humans. A liberal estimate places the genes that are unique to humans at less than 20. That's out of 20,000 genes that make up each human.

Genetic testing can be performed for a variety of reasons, and the advances in genetics have the potential to change the way physicians diagnose and treat major illnesses. Scientists haven't yet reached the point where they can repair defective genes, but it's certainly possible to determine whether certain genes will be passed on. While genetic testing is still in its earliest stages, there are several promising developments in genetic science.

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Nurture Scores a Point against Nature

The old debate about whether our behavior is inherent in our genes or a result of our environment just got more complicated. Genetic science has provided evidence that it's possible our lifestyle can actually change our genes. Environment, diet, and circumstances can turn certain genes on and off. A traumatic event could very well turn on a switch that makes your body behave in an uncharacteristic way. This kind of research is doing wonders in cancer treatment research as scientists look to turn off dangerous cells through lifestyle and environment changes.

Mutations in Kids with Cancer

Researchers at St. Jude Children's Research Hospital reported that more than eight percent of children with cancer have genetic mutations that run in their families. This will invariably lead to better methods of treating and detecting cancer early and will work to save lives.

Friends Really Are Like Family

Researchers at University of California San Diego and Yale University have discovered that friends share 0.1 percent more DNA than they do with strangers. To put this in perspective, that's the equivalent of the amount of DNA you might share with your fourth cousin.

Gene Assembly Sub-Pipelines

More genetic advancements are coming into the realm of technology and the modern field of synthetic biology as well. Laboratories like Hudson Robotics have succeeded in automating the process of gene assembly. This means they can create functioning genes and complete genomes. One example is in the creation of viruses. In short, they can take several short DNA sequences and put them together to create the original chromosomes that the DNA originated from.

As genetic science improves, there will be better treatments for people with illnesses and disease. Scientists will be able to detect potential issues early on, and provide treatment before cancer begins to take hold. This should improve life expectancy and even prevent certain diseases.

By Brooke Chaplan

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Author Bio - 33rd Square contributor Brooke Chaplan is recent graduate of New Mexico University where she studied journalism. She loves to hike, bike, run and explore around her home in Los Lunas, New Mexico. She also enjoys blogging about health, fitness, fashion and many other topics.

Longevity  

For the first time, research has pointed to a genetic link between intelligence and longevity. The finding have important implications for public health, and for those interested in the genetics of intelligence, lifespan or inequalities in health outcomes including lifespan.

The tendency of more intelligent people to live longer has been shown, for the first time, to be mainly down to their genes by new research published in the International Journal of Epidemiology.

By analyzing data from twins, researchers found that 95 per cent of the link between intelligence and lifespan is genetic. The researchers found that, within twin pairs, the brighter twin tends to live longer than the less bright twin and this was much more pronounced in fraternal (non identical) twins than in identical twins.

This is the first study to test for a genetic association between intelligence and lifespan.

Studies that compare genetically identical twins with fraternal twins –  who only share half of their twin’s DNA –   help distinguish the effects of genes from the effects of shared environmental factors such as housing, schooling and childhood nutrition.

"Our research shows that the link between intelligence and longer life is mostly genetic."

Rosalind Arden, a research associate at the London School of Economics and Political Science (LSE), said: “We know that children who score higher in IQ-type tests are prone to living longer. Also, people at the top of an employment hierarchy, such as senior civil servants, tend to be long-lived. But, in both cases, we have not understood why.

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“Our research shows that the link between intelligence and longer life is mostly genetic. So, to the extent that being smarter plays a role in doing a top job, the association between top jobs and longer lifespans is more a result of genes than having a big desk.

“However, it’s important to emphasize that the association between intelligence and lifespan is small. So you can’t, for example, deduce your child’s likely lifespan from how he or she does in their exams this summer.”

The researchers looked at three different twin studies from Sweden, the United States and Denmark where both intelligence and age of death was recorded, and where at least one twin in each pair had died.  Only twins of the same sex were included in the analysis.

On the reasons for the findings, Rosalind Arden said: “It could be that people whose genes make them brighter also have genes for a healthy body.  Or intelligence and lifespan may both be sensitive to overall mutations, with people with fewer genetic mutations being more intelligent and living longer. We need to continue to test these ideas to understand what processes are in play.”

SOURCE  London School of Economics and Political Science

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Genomics  

Genetic testing and other advances have made it possible for patients to plan for a better quality of life, with health information that was previously unavailable.

Genetic science is moving to the mainstream, especially in the field of medicine. In this broad discipline, genetics is fast becoming a necessary arm for the screening of certain diseases and the evaluation of viable (and possibly life-saving) interventions.

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Landmarks in Genetics

There are many significant examples of how genetics has informed medicine and helped bring on solutions. One such example is the discovery in 1959 of the extra chromosome in individuals with Down syndrome. Since then, doctors have been able to watch for the presence of this extra chromosome in amniotic fluid tests (AFTs) or amniocentesis, providing vital information for parents in assessing future health management issues.

Later, the identification of 45X in Turner syndrome led to the discovery of hormone therapy as a means to alleviate some of the manifestations of the condition, particularly in females. Likewise, finding the 47,XXY chromosome has resulted in a better understanding of a condition known as Klinefelter Syndrome. Those affected by this condition have two X and one Y chromosome instead of the usual XY chromosomes for males and the XX chromosome pair for females. This condition can cause infertility and the development of intersex characteristics.

Genetics in the Limelight

Today genetic research has succeeded in identifying over a hundred gene variants that suggest an increased risk of different types of cancer. For example, recently it was discovered that having a variant BRCA gene significantly increases the risk of breast and ovarian cancer in women. Awareness of this gene increased greatly when Angelina Jolie had a preventive mastectomy after she had herself tested.

The Benefits of Genetic Testing

When children show signs of metabolic and neurological disorders, genetic testing can help ascertain the condition that they are suffering from. Many pediatric disorders can be diagnosed through genetic testing by companies such as Courtagen Life Sciences; this makes it possible for families and their doctors to work on managing the health care of affected children. At the same time, diagnosis of certain disorders, such as mitochondrial diseases, will help families and their doctors explore viable treatment options.

State-of-the-Art Genetic Testing

The administration of genetic testing has become relatively simple today, particularly where testing children is concerned. Modern clinics, for example, will actually provide a saliva kit for the collection of an adequate sample to be mailed for analysis. The kit, which comes with instructions, allows samples to be collected from children without any pain or trauma.

Genetics has changed the landscape of diagnostics and management of hereditary diseases, and it has helped doctors choose appropriate treatments for their patients. For many individuals, genetic testing has made it possible for patients to plan for a better quality of life.

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Author Bio - A recent college graduate from University of San Francisco, Anica loves dogs, the ocean, and anything outdoor-related. She was raised in a big family, so she's used to putting things to a vote. Also, cartwheels are her specialty. You can connect with Anica here.

 Psychology  

Science is increasingly showing that addiction, in its various forms, has a probable strong genetic underpinning. With each discovery, researchers get closer to finding a biological cause for addictive behavior.

Coffee, tanning, alcohol or even the internet – are you obsessed with any of them? As it turns out, genetics may be responsible for your propensity toward one vice or the other. Researchers at the Yale School of Public Health recently discovered that individuals presenting with variants of PTCHD2 – patched domain containing 2, a protein-coding gene – were approximately 66 percent less likely to exhibit signs of tanning addiction. Published in the online journal Experimental Dermatology, the findings put researchers a step closer to finding a biological cause for addictive behavior.

Tanning Tied to Genetic Variants

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The study still needs to be replicated, but if the statistics aren’t lying the results hold promise for the future. Motivated by the growing health problems associated with frequent tanning, Yale researchers analyzed genetic data for 292 participants and reviewed more than 300,000 genetic variants before pinpointing PTCHD2 as a potential culprit. A senior research scientist, Brenda Cartmel, expressed excitement at the results’ potential to influence future interventions, which could reduce the prevalence of skin cancer.

Genes Linked to Substance Abuse 

Though tanning seems harmless, it mimics substance abuse in that individuals are not able to control their behaviors despite being warned of the consequences. Addiction to alcohol, caffeine, tobacco and illicit substances has been linked to gene variants. Researchers from the Institute of Psychiatry at London’s Kings College confirm links between addictive behaviors and certain gene variants, like CHRNA5 and ADH1B. Thus far, the following substances have been traced to a genetic component:

• Caffeine. In 2014, Harvard School of Public Health reported a link between the effects of caffeine and two genetic variants, POR and ABCG2. Published in Molecular Psychiatry, the findings provide insight into the genetic basis of caffeine addiction. 

• Alcohol. Genetic variants ADH and ALDH, believed to play a role in the metabolism of alcohol, were linked to alcohol abuse disorders, according to a 2008 study published in the British Journal of Pharmacology. 

• Cocaine. In addition to dopamine receptors, genetic variants like ΔFosB and CAMK4 have been linked to cocaine addiction, according to a 2005 study published in Science & Practice Perspectives.

• Tobacco. A study published in Human Molecular Genetics found that individuals with CHRNB3, a nicotinic receptor gene, were twice as likely to become addicted to tobacco once exposed. 

The University of Utah’s online Genetic Science Learning Center notes that multiple variants play a role in addiction, but the presence or absence of a gene variant doesn’t itself predict addictive behaviors. Rather, a combination of factors, from economic status to trauma, is involved.

Combating Addiction With Science

Until scientists uncover more information about genetic variants and their relationship to addiction, it’s unclear how gene mapping can be used to curb the prevalence of addiction. Proposed uses of genetic markers for addiction include prescreening tests to determine risk level or to adjust treatment plans based on personalized data. Given the treatment options for those with addiction – namely medication, counseling or inpatient care – using genetic data to enhance recovery outcomes may be the solution to a growing international addiction problem. However, convincing national health care systems and private practitioners to get on board with genetic medicine may be another challenge entirely.

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 Aging  

Researchers have dramatically increased the lifespan of the common fruit fly by activating a newly-discovered gene responsible for eliminating unhealthy cells.

Researchers have managed to increase the lifespan of flies significantly. To do this, they have activated a gene that destroys unhealthy cells. The results of the study show by new possibilities of how to slow aging in humans.

The new research has been published in the journal Cell.

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Biologists continue to try extend the life of people through the exploration of model organisms such as mice or flies. Under the leadership of Eduardo Moreno is researcher at the Institute of Cell Biology, University of Bern now possible to develop a new method for the life of flies extension.

"We reasoned that selecting the less affected cells and eliminating the damaged ones could be a good strategy to maintain tissue health and therefore delay aging and prolong lifespan."

This is based on the targeted selection of the best functioning cells.

"Our bodies are composed of trillions of cells," says Moreno. "As we age, accumulate in them due to overloading or external interference factors, such as UV radiation from the sun, getting more random defects." But these defects do not occur in all cells at the same time and with the same intensity as Moreno says: "Some cells are more affected than others.We reasoned that selecting the less affected cells and eliminating the damaged ones could be a good strategy to maintain tissue health and therefore delay aging and prolong lifespan."

To test their hypothesis, the researchers resorted back to the fruit fly Drosophila melanogaster. The first challenge was to find out what were the healthier cells in the organs of the fruit fly. Moreno's team discovered a gene that is activated in less healthy cells. They called the gene ahuizotl (azot) after a mythological Aztec creature selectively targeting fishing boats to protect the fish population of lakes, because the function of the gene was also to selectively target less healthy or less fit cells to protect the integrity and health of the organs like the brain or the gut.

Normally, there are two copies of this gene in a cell. By pasting-in a third copy, the scientists were able to sort out the healthier cells and nerve cells more efficiently. The result of this cellular "quality control", according to Moreno was "very exciting."

The treated flies showed a healthier tissue, aging more slowly and have a longer life. "Our flies lived an average of 50 to 60 percent longer than their other counterparts," says Christa Rhiner, co-author of the study.

However, the potential of these results goes beyond the creation of Methuselah flies, the researchers say, because the azote gene is also present in the human body, the selection of healthier, fitter cells in organs could, in the future, serve as a mechanism to slow aging.


SOURCE  University of Bern

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 Longevity  

Sequencing fewer than twenty genomes of the world's oldest peopleUsing fewer than 20 genomes, we were unable to find rare protein-altering variants significantly associated with extreme longevity, researchers were unable to find rare protein-altering variants significantly associated with extreme longevity, according to a new study.

B y sequencing 17 genomes of the world's oldest people, researchers were so far unable to find any markers that would potentially be associated with extreme longevity, according to a study published in the open-access journal PLOS ONE.

Supercentenarians are the world’s oldest people, living beyond 110 years of age. Seventy-four are currently alive worldwide. The study authors, led by Hinco Gierman from Stanford University, performed whole-genome sequencing on the individuals to determine if there were any genetic reasons for their extreme longevity.

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"Using fewer than 20 genomes, we were unable to find rare protein-altering variants significantly associated with extreme longevity."

Due to the small sample size, the researchers conclude they were unable to find rare protein-altering variants significantly associated with extreme longevity compared to control genomes. "It is not surprising that a highly complex trait such as longevity is not explained by a single Mendelian gene," the authors conclude.

"Using fewer than 20 genomes, we were unable to find rare protein-altering variants significantly associated with extreme longevity," said Gierman.

They did find that one supercentenarian carries a variant associated with a heart condition, which had little or no effect on his/her health, as this person lived over 110 years.

The authors have publicly published the genomes, making them available as a resource for future studies on the genetic basis of extreme longevity.

SOURCE  PLOS ONE, Top Image - Mike Ip

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 Genomics  

A new concept store that has just opened in London, offering customers a DNA test to see how they will age in years to come. Using lab-on-a-chip technology, Geneu Beauty customizes products based around your genetics—in around 30 minutes.

Now at a shop in London, you can have your DNA profiled and within 30 minutes, have the data used to create bespoke skin products that will help you look and feel younger. The 2014 European Innovation Award Winning, Geneu Beauty’s DNA BeautyLab on a microchip does what traditionally would have taken a whole month with a huge lab, masses of equipment to achieve.

Developed over the last ten years by Christofer Toumazou at Imperial College London, the lab-on-a-chip technology tests your DNA for two genetic variations responsible for the ageing of our skin – collagen breakdown and antioxidant protection.

 "We licensed the technology initially to the consumer beauty industry because they can take the stigma away from it being medical and it drives the consumer much more to acceptance," says Toumazou.

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The approach is entirely focused around DNA profiling, which is then recorded on a microchip. This enables the right ingredient, in the right concentration and in the right combination to be prescribed based on an individual’s DNA.

"We licensed the technology initially to the consumer beauty industry because they can take the stigma away from it being medical and it drives the consumer much more to acceptance."

There's no needles, scalpels or surgeons, just a swab inside the mouth and a quick questionnaire about your lifestyle choices (which ultimately, still affect your future self). Finally, a personalized skincare regime is prescribed, giving you the perfect mix of anti-ageing ingredients to use in place of your generic regime.

Coupling your results with individual lifestyle factors such as sun exposure, smoking and age a PhD-qualified scientific adviser and beauty expert at Geneu Beauty discuss results before providing customers with a custom-tailored product recommendation,

The U+ DNA personalized anti-aging serum is formulated to provide the ultimate combination of active ingredients and will offer dual support to help target wrinkles, elasticity and fine lines – leaving skin looking visibly improved and hydrated according to the company.

As might be expected, the initial appointment with assessment and lab-on-a-chip DNA profiling, plus a two week supply of Geneu DNA Personalized Anti-ageing Serum costs a lofty £600 ($965 USD), and then the monthly cost for the skincare costs £300.



SOURCE  Marie Claire

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 Medicine  

Cutting edge medical advancements are helping to detect diseases early and provide a tailored treatment that is highly effective in treating and curing illness. Here is a glimpse into the high-tech health care resulting from the newest in medical technology.

Not long ago, AIDS was considered as an untreatable disease. Cancer was considered as a disease with low chances of survival. Elders living alone had great difficulties reaching for help. The difficulties associated with monitoring high-risk patients 24/7 often led to their death. All these are changing now due to the emergence high-tech health care. Recent developments in patient surveillance and tracking are helping to closely monitor the high-risk patients. Advancements in genome sequencing and Pharmacogenomics are helping to detect diseases early and provide a tailored treatment that is highly effective in curing diseases, including cancer. Here is a glimpse into the high-tech health care resulting from the advancements in medical technology.

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Sensors, Wearable Devices, and Remote Monitoring Tools

New wearable medical devices can now detect and send alerts when a patient falls down. Bandages can detect infections by monitoring the pH level. Patients at high risk can be fitted with devices such as a cardiac cast that can monitor the heartbeat and send data to a monitoring center. Digestible sensors can transmit information about the human body, including organs. Patients can now stay at home rather than in the hospital, helping to cut down the hospital cost and the readmission requirements.

Robotic Surgery, Drug Discovery

A surgeon can now perform advanced surgeries by using a robotic hand that can reach through a small cut made in the body. This technique is used for several complex surgical tasks, including coronary artery bypass, kidney transplant, and gallbladder removal. Researchers can now use Hudson products like robotic assay screening and development system for drug discovery using different detection methods such as enzyme-linked immunoabsorption, reporter gene luminescence, and fluorescence energy transfer. Robotic systems can also be used to determine the pharmaceutical profile of a patient.

3D Printing

Biological materials such as blood vessels, heart tissues, and embryonic stem cells can now be printed using 3D printers. 3D printing has also been used for patching a broken heart as well as replacing organs. There have been advances in developing skins for patients by printing skin cells using this technique.

Optogenetics

Advances in neuroscience have made it possible for scientists to control the neurons in the brain. This technique is used for understanding the cause and curing different mental disorders such as Parkinson’s disease and schizophrenia.

There are greater benefits to humankind due to the advancements in medical technology. The high tech health care is ascending, and is helping to achieve things that were considered impossible not long ago. The emergence of big data analytics in discovering medical patterns is helping to understand diseases and treatments better. Use of robotics in surgical and drug discovery area seems very promising. Health monitoring devices are now even being integrated into smartphones, making the medical technology go mainstream. As medical tech grows, so will our quality of life.

By Anica Oaks

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About the Author - Anica is a freelance writer and web enthusiast. You can read some of her published work at her Google+ page.

 Evolution  

Evolve and resequence (E&R) is a new approach for investigating the genomic responses to selection during experimental evolution. By using whole genome sequencing of pools of individuals (Pool-Seq), this method can identify select variables that, over the long term, control evolution.

Life implies change. And this holds true for genes as well. Organisms require a flexible genome in order to adapt to changes in the local environment. Christian Schlötterer and his team from the Institute for Population Genetics at the University of Veterinary Medicine, Vienna study the genomes of entire populations.

The scientists want to know why individuals differ from each other and how these differences are encoded in the DNA. In two review papers published in the journals Nature Reviews Genetics and Heredity, they discuss why DNA sequencing of entire groups can be an efficient and cost-effective way to answer these questions.

Overview of E&R studies - C Schlötterer, R Kofler, E Versace, R Tobler and S U Franssen / Heredity

"We are using this method to address a broad range of questions, ranging from the identification of genes which influence aging, or genes protecting against diseases and finally to understand the genetic changes which reduce the impact of climate change."

DNA analysis has become increasingly efficient and cost-effective since the human genome was first fully sequenced in the year 2001. Sequencing a complete genome, however, still costs around US$1,000. Sequencing the genetic code of hundreds of individuals would therefore be very expensive and time-consuming. In particular for non-human studies, researchers very quickly hit the limit of financial feasibility.

The solution to this problem is pool sequencing (Pool-Seq). Schlötterer and his team sequence entire groups of fruit flies (Drosophila melanogaster) at once instead of carrying out many individual sequencing reactions. While the resulting genetic information cannot be attributed to a single individual, the complete data set still provides important genetic information about the entire population.

In the two publications, Schlötterer and colleagues discuss the breadth of questions that can be addressed by Pool-Seq.

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In order to understand how organisms react to changes in the local environment, the genomes of entire populations can be analysed using Pool-Seq, before and after changed conditions. To do so, the researchers use the method of evolve and resequence (E&R).

After exposing the descendants of this group for several generations to a certain stress, such as high temperature, extreme cold or UV radiation, the evolved group is sequenced again. A comparison of the two data sets uncovers genes that have changed in response to the selective stress. The approach makes it possible, to filter out the genes that are involved in a darker pigmentation in response to UV radiation.

“Using this principle, we can perform evolution experiments at high speed. We are using this method to address a broad range of questions, ranging from the identification of genes which influence aging, or genes protecting against diseases and finally to understand the genetic changes which reduce the impact of climate change,” Schlötterer explains.

The evolve-and-resequence approach also makes it also possible to filter out the genes that regulate aging. This process involves selecting flies from a population, repeatedly over generations, that reach an especially old age.  Several generations later, the researchers then compare the genomes of the “Methuselah” flies with those from normally aging flies in order to extract the genes that are involved in the aging process. This method also works to locate genes that provide resistance against certain diseases.

Bioinformatician and co-author, Robert Kofler, explains: “We are dealing with genetic change processes and are searching for variations in the genomes. The variations can help us to understand how evolution works.”


SOURCE  University of Veterinary Medicine, Vienna

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 Genomics  

A survey of the Human Microbiome Project’s genomic database has revealed that the microbes living in and on healthy humans contain more than 3,000 sets of instructions for synthesizing small molecules, some of which may hold the key to future medical applications.

As the threat of antibiotic resistance grows, scientists are turning to the human body and the trillion or so bacteria that have colonized us — collectively called our microbiota — for new clues to fighting microbial infections. They’ve logged an early success with the discovery of a new antibiotic candidate from vaginal bacteria, reports Chemical & Engineering News (C&EN).

The Human Microbiome Project (HMP) program sponsored by the US National Institutes of Health (NIH) aims to develop tools and datasets for the research community for studying the role of these microbes in human health and disease.

The first phase of HMP characterized the composition and diversity of microbial communities which inhabit major mucosal surfaces of the human body, including nasal passages, oral cavities, skin, gastrointestinal tract, and urogenital tract, and evaluated the genetic metabolic potential of these communities. The current phase of the project is focused on the creation of the first integrated dataset of biological properties from both the microbiome and host from cohort studies of microbiome-associated diseases.

"I’d always thought that drugs are discovered by drug companies, approved by the Food & Drug Administration, prescribed by a physician—and then they get to you. Human-associated bacteria are mounting an end run around that process."

“I’d always thought that drugs are discovered by drug companies, approved by the Food & Drug Administration, prescribed by a physician—and then they get to you,” says Michael A. Fischbach, a chemist at the University of California, San Francisco, who led the study. “Human-associated bacteria are mounting an end run around that process.”

Even the placenta has recently been discovered to have it's own complex microbiome.

The human microbiota produces thousands of small molecules. Some have been discovered and tested, but by and large, very little is known about most of them. However, it could be well worth finding out more.

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Doctors are already prescribing pharmaceuticals based on small molecules made by exotic bacteria from the earth and sea, meaning our own microbes could be an untapped and accessible source of novel drugs. But rifling through all of the microbiota’s natural products for a hit is like searching for a needle in a haystack.

To shrink that haystack, one team of scientists took a systematic, computer-assisted approach. They designed software to compare the microbiota’s collective genes, or microbiome, against genes that are already known or suspected to play a role in producing small molecules that help keep microbes, and maybe their hosts, healthy. The team found more than 3,000 such gene clusters. One of those, from the vaginal bacteria Lactobacillus gasseri, contains the code for a small molecule that is very similar to a recently discovered antibiotic now undergoing clinical testing. When the scientists tested the Lactobacillus molecule in the lab, they found it attacked gram-positive bacteria, some of which can cause human illness.

Results of the study have been published in the journal Cell.

“We are just at the beginning of the journey,” agrees George M. Weinstock, associate director of microbial genomics at the Jackson Laboratory for Genomic Medicine, a nonprofit research organization. But this study is an exciting and encouraging start, he says. “There will be many more stories like this.”


SOURCE  Chemical & Engineering News

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 Genetics  

Researchers have shown that the human version of a gene called FOXP2 makes it easier to transform new experiences into routine procedures. When they engineered mice to express humanized FOXP2, the mice learned to run a maze much more quickly than normal mice.

Mice that receive a human version of a speech and language gene display accelerated learning, according to a new study.

While the researchers are careful not to call this an uplift gene, the work reveals something new and fascinating about the evolution of human speech and language.

The gene for the protein called FOXP2 has been firmly linked to human speech and language. Humans with just one functional copy of this gene experience difficulties in learning and struggle with spoken and written language.

The investigators discovered the mice with the human form of FOXP2 learned profoundly faster than regular mice when both declarative and procedural forms of learning were involved. The scientists published their findings in the Proceedings of the National Academy of Sciences.

The findings suggest that FOXP2 may help humans with a key component of learning language -- transforming experiences, such as hearing the word "glass" when we are shown a glass of water, into a nearly automatic association of that word with objects that look and function like glasses, says Ann Graybiel, an MIT Institute Professor, member of MIT's McGovern Institute for Brain Research, and a senior author of the study.

"This really is an important brick in the wall saying that the form of the gene that allowed us to speak may have something to do with a special kind of learning, which takes us from having to make conscious associations in order to act to a nearly automatic-pilot way of acting based on the cues around us."

“This really is an important brick in the wall saying that the form of the gene that allowed us to speak may have something to do with a special kind of learning, which takes us from having to make conscious associations in order to act to a nearly automatic-pilot way of acting based on the cues around us,” Graybiel says.

The gene itself is not unique—chimps have a version of it. But because the human and chimpanzee lineages diverged roughly 6 million years ago, they don't have two key changes in amino acids that humans have evolved.

To learn more about how FOXP2 alters the brain, scientists genetically engineered mice with the human form of FOXP2. In experiments with these rodents, the researchers focused on two modes of learning thought to be crucial for speech and language—declarative learning, which involves knowledge learned consciously, and procedural learning, which involves knowledge learned by experiencing something enough times for it to become habit.

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The scientists had mice run through a maze to get a reward of chocolate milk. The animals could figure out the location of the reward either through sensory cues such as rough or smooth floors, which corresponds to declarative learning. Or, they could discover the reward was always linked to either a left or right turn, which corresponds to procedural learning.

Declarative learning involves circuits in the central part of the striatum region of the brain, while procedural learning involves circuits in more peripheral parts of the striatum. The scientists found that both sets of circuits were altered in the mice with the human form of FOXP2.

Prior studies found that mice with the human version of FOXP2 demonstrate profound changes in the chemistry and anatomy of brain circuits essential for acquiring habits and other physical and mental behaviors, such as songbirds learning song. The kinds of changes seen in these studies may once have helped the human brain evolve speech and language.

"I don't think the goal is to make smarter animals, but rather to dissect out the biology underlying smartness," Smith says. "Having said that, if we can find a procedure like this that would help treat neurological or psychiatric disorders, that would be a wonderful purpose. For example, Parkinson's disease involves the same brain circuits being studied in this article — perhaps genes could be tweaked in similar ways to help."

This study "provides new ways to think about the evolution of Foxp2 function in the brain," says Genevieve Konopka, an assistant professor of neuroscience at the University of Texas Southwestern Medical Center who was not involved in the research. "It suggests that human Foxp2 facilitates learning that has been conducive for the emergence of speech and language in humans. The observed differences in dopamine levels and long-term depression in a region-specific manner are also striking and begin to provide mechanistic details of how the molecular evolution of one gene might lead to alterations in behavior."


SOURCE  MIT

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 Longevity  

Scientist looking at the genetics of exceptionally long-lived individuals have uncovered a marker that may help explain their long lives.  Variants in the gene apolipoprotein B (APOB) help the body deal with low-density lipoprotein (LDL) also known as bad cholesterol.

Scientists have been wondering about what the secrets are for living longer for some time now and while we understand that various lifestyle and environmental factors contribute to our longevity, it is also evident that genetics plays a role. In fact, family studies have indicated that genetic factors account for around 20-30% of the variation in adult lifespan. Now, a new study, published in Aging Cell, may have some answers.

"This would definitely reinforce the idea that cardiovascular health is an important factor in overall ageing."

The study is one of the first that has targeted exceptionally older families for genetic markers of longevity.

Previous work had identified a few candidate genes that researchers suspect may play a role in longevity. The genes identified were apolipoprotein E (APOE), which transports cholesterol around the body, and FOXO3A which may affect insulin sensitivity. Variations in these genes were found to be associated with longevity; however, neither had a large influence, which left scientists suspecting that there must be other factors at play.

Looking deeper, researchers from the Spanish National Cancer Research Center scoured the protein-coding genes, or exomes, of members of three separate families that all had exceptionally long-lived members. Three of the individuals sequenced lived to be 103 or older, and their siblings lived to be 97 or older. They then compared these with sequence data from 800 other people that acted as controls.

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They found that rare variants in one particular gene cropped up in all three families—apolipoprotein B (APOB). Like the APOE protein, APOB is a cholesterol transporter. APOB helps to carry “bad cholesterol,” or low-density lipoprotein (LDL), in the blood. While our bodies need cholesterol, LDL has a bad rep because it can build up along the walls of blood vessels, blocking arteries and eventually leading to heart attacks in some.

These genetic variations may reduce the levels of LDL in the blood, an idea that the researchers are now investigating. According to lead author Timothy Cash, if the long-lived individuals do have lower cholesterol levels, it would reinforce the idea that cardiovascular health is an important factor in the aging process. Interestingly, variations inAPOE are also known risk factors for cardiovascular disease, which is likely due to elevated lipid levels.

The team is now investigating whether the centenarians' cholesterol levels bear out this theory. If they do, "this would definitely reinforce the idea that cardiovascular health is an important factor in overall ageing", says Cash.


SOURCE  New Scientist

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