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By Smitha Mundasad Health reporter There has been a worrying rise in the number of working-age men and women having strokes, a charity has warned. In England in 2014 there were 6,221 hospital admissions for men aged 40-54 - a rise of 1,961 on 14 years earlier, a Stroke Association study shows. Experts said unhealthy lifestyles were partly to blame for the rise, though the growing population and changes to hospital practice also played a part. Overall the rate of strokes is going down in the UK, however. Researchers say based on their findings strokes should not be considered as a disease of the old. Strokes are caused by blood clots or bleeds to the brain and can lead to long-lasting disability. The majority occur in people aged over 65, and though rates are decreasing in this group, this report suggests growing numbers of younger people are at risk. Experts analysed national hospital admission data spanning 2000 to 2014. Trends for people in their 40s and early 50s appeared to be getting worse. In women aged 40-54, there were an extra 1,075 strokes recorded in 2014, compared with 2000. Experts said growing obesity levels, sedentary lives and unhealthy diets - which raise the risks of dangerous blood clots - all played a part. And they argued strokes among this age group had long-lasting personal and financial impacts on individuals and their families, as well as on the economy. Recovering patients can find it difficult to return to work and should have more support from employers, the report suggests. Jon Barrick, of the Stroke Association, said: "These figures show stroke can no longer be seen as a disease of older people. "There is an alarming increase in the numbers of people having a stroke in working age. © 2015 BBC.
Link ID: 20912 - Posted: 05.12.2015
Tina Hesman Saey COLD SPRING HARBOR, N.Y. — Taming animals makes an impression on their DNA. Domesticated animals tend to have genetic variants that affect similar biological processes, such as brain and facial development and fur coloration. Alex Cagan of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, reported the results May 6 at the Biology of Genomes conference. Cagan and colleagues examined DNA in Norway rats (Rattus norvegicus) that had been bred for 70 generations to be either tame or aggressive toward humans. Docility was associated with genetic changes in 1,880 genes in the rats. American minks (Neovison vison) bred for tameness over 15 generations had tameness-associated variants in 525 genes, including 82 that were also changed in the rats. The researchers also compared other domesticated animals, including dogs, cats, pigs and rabbits, with their wild counterparts. The domestic species and the minks had tameness-associated changes in genes for epidermal growth factor and associated proteins that stimulate growth of cells. Those proteins are important for the movement of neural crest cells within an embryo. That finding seems to support a recent hypothesis that changes in neural crest cells could be responsible for domestication syndrome, physical traits, including floppy ears, spotted coats and juvenile faces, which accompany tameness in many domestic animals. © Society for Science & the Public 2000 - 2015.
Jane Brody With people worldwide living longer, marketers are seizing on every opportunity to sell remedies and devices that they claim can enhance memory and other cognitive functions and perhaps stave off dementia as people age. Among them are “all-natural” herbal supplements like Luminene, with ingredients that include the antioxidant alpha lipoic acid, the purported brain stimulant ginkgo biloba, and huperzine A, said to increase levels of the neurotransmitter acetylcholine; brain-training games on computers and smartphones; and all manner of puzzles, including crosswords, sudoku and jigsaw, that give the brain a workout, albeit a sedentary one. Unfortunately, few such potions and gizmos have been proven to have a meaningful, sustainable benefit beyond lining the pockets of their sellers. Before you invest in them, you’d be wise to look for well-designed, placebo-controlled studies that attest to their ability to promote a youthful memory and other cognitive functions. Even the widely acclaimed value of doing crossword puzzles has been called into question, beyond its unmistakable benefit to one’s font of miscellaneous knowledge. Although there is some evidence that doing crosswords may help to delay memory decline, Molly Wagster, a neuroscientist at the National Institute on Aging, said they are best done for personal pleasure, not brain health. “People who have done puzzles all their lives have no particular cognitive advantage over anyone else,” she said. The institute is one of several scientific organizations sponsoring rigorous trials of ways to cash in on the brain’s lifelong ability to generate new cells and connections. One such trial, Advanced Cognitive Training for Independent and Vital Elderly, or Active, was a 10-year follow-up study of 2,832 cognitively healthy community-dwelling adults 65 and older. © 2015 The New York Times Company
Andrew Griffin Scientists have created an electronic memory cell that mimics the way that human brains work, potentially unlocking the possibility of the making bionic brains. The cell can process and store multiple bits of information, like the human brain. Scientists hope that developing it could make for artificial cells that simulate the brain’s processes, leading to treatments for neurological conditions and for replica brains that scientists can experiment on. The new cells have been likened to the difference between having an on-off light switch and a dimmer, or the difference between black and white pictures or those with full colour, including shade light and texture. While traditional memory cells for computers can only process one binary thing at a time, the new discovery allows for much more complex memory processes like those found in the brain. They are also able to retain previous information, allowing for artificial systems that have the extraordinary memory powers found in human beings. While the new discovery is a long way from leading to a bionic brain, the discovery is an important step towards the dense and fast memory cells that will be needed to imitate the human brain's processes. “This is the closest we have come to creating a brain-like system with memory that learns and stores analog information and is quick at retrieving this stored information,” Sharath Sriram, who led the project, said.
Aaron E. Carroll When I was a kid, my parents refused to let me drink coffee because they believed it would “stunt my growth.” It turns out, of course, that this is a myth. Studies have failed, again and again, to show that coffee or caffeine consumption are related to reduced bone mass or how tall people are. Coffee has long had a reputation as being unhealthy. But in almost every single respect that reputation is backward. The potential health benefits are surprisingly large. When I set out to look at the research on coffee and health, I thought I’d see it being associated with some good outcomes and some bad ones, mirroring the contradictory reports you can often find in the news media. This didn’t turn out to be the case. Just last year, a systematic review and meta-analysis of studies looking at long-term consumption of coffee and the risk of cardiovascular disease was published. The researchers found 36 studies involving more than 1,270,000 participants. The combined data showed that those who consumed a moderate amount of coffee, about three to five cups a day, were at the lowest risk for problems. Those who consumed five or more cups a day had no higher risk than those who consumed none. Of course, everything I’m saying here concerns coffee — black coffee. I am not talking about the mostly milk and sugar coffee-based beverages that lots of people consume. These could include, but aren’t limited to, things like a McDonald’s large mocha (500 calories, 17 grams of fat, 72 grams of carbohydrates), a Starbucks Venti White Chocolate Mocha (580 calories, 22 grams of fat, 79 grams of carbs), and a Large Dunkin’ Donuts frozen caramel coffee Coolatta (670 calories, 8 grams of fat, 144 grams of carbs). I won’t even mention the Cold Stone Creamery Gotta-Have-It-Sized Lotta Caramel Latte (1,790 calories, 90 grams of fat, 223 grams of carbs). Regular brewed coffee has 5 or fewer calories and no fat or carbohydrates. © 2015 The New York Times Company
Keyword: Drug Abuse
Link ID: 20908 - Posted: 05.12.2015
Margaret Wente Child psychiatrist Susan Bradley was a pioneer in treating kids with gender-identity disorders. In the 1970s, she founded the child and adolescent gender identity clinic at the Clarke Institute in Toronto, which eventually became part of the Centre for Addiction and Mental Health (CAMH). Back then, the field was virtually unknown. Today, it is Ground Zero in a fierce battle between oldfangled psychiatry and transgender activists who insist that practitioners like Dr. Bradley are guilty of child abuse. Caught in the middle are confused parents, well-meaning schools, and – most important of all – troubled and bewildered kids. The new rush to turn little Jason into Janey, or Sally into Sam, is generally regarded (in the media, at least) as progress – proof of what a tolerant and progressive society we’ve become. But what if it’s just another fad? What if the radical step of changing genders isn’t always the right answer for a child’s emotional distress – especially when that child is only 10 or 6, or 3? “Some of these kids are quite significantly ill,” says Dr. Bradley. “They often have serious family problems and anxiety disorders. Or they’ve had serious trauma. A girl I saw had been raped, and after that she decided she was going to be a male. If you didn’t pay attention to the trauma you’re not doing that kid a service.” These days, that eminently reasonable view is being challenged by people who believe that children’s sexual confusion should automatically be taken at face value. The clinic that Dr. Bradley helped to found – which does, in fact, support gender transition for a sizable minority of its patients – is being pilloried as transphobic. “Is CAMH trying to turn trans kids straight?” screamed a headline in NOW magazine. Under pressure from activists, CAMH has put its gender clinic under six-month review. And a new bill before the Ontario legislature, which is supported by Premier Kathleen Wynne, would explicitly bar the therapeutic approach taken by the clinic, wrongly equating it to the notorious “conversion” therapy that seeks to turn gay people straight. © Copyright 2015 The Globe and Mail Inc.
Patricia Neighmond Terri Bradford has suffered debilitating headache pain all her life. Some days the pain is so bad, she says, "By 11 o'clock in the morning, I'm on the couch in a darkened room with my head packed in ice." Over the years, Bradford, who is 50 years old and lives in Bedford, Mass., has searched desperately for pain relief. She's been to the doctor countless times for countless tests. "Everything I've had, I've had twice," she says. "I've had two spinal taps; I've had so many nerve blocks I've lost count." Bradford is not alone. It's estimated that every year 12 million Americans go to the doctor seeking help for headaches. Nearly one quarter of the population suffers from recurrent severe tension headaches or migraines. People who go to the doctor for headache pain are more likely to be sent for advanced testing and treatment, a study finds. That testing is expensive, it may not be necessary and could even be harmful, says lead researcher Dr. John Mafi of Beth Israel Deaconess Medical Center in Boston. Mafi looked at the rates of advanced imaging like CT scans and MRIs in people with headaches, as well as referrals to other doctors, presumably specialists. He found that from 1999 to 2010, the number of diagnostic tests rose from 6.7 percent of all doctor visits to 13.9 percent. At the same time, referrals to other doctors increased from 6.9 percent to 13.2 percent. So almost double what it was a decade ago. Mafi says this isn't because more people are suffering headaches. The headache rate has remained virtually the same over the past decade. But what has changed is supply and demand. Today there are a lot more advanced diagnostic machines than there were a decade ago, and more patients are asking to be tested. © 2015 NPR
Robin McKie The European parliament will on Monday debate a call – backed by a petition signed by 1.2 million people – to scrap animal research in the EU. The proposal has alarmed scientists, who worked for six years to set up the 2010 European directive that controls animal experimentation and welfare in the EU. Researchers fear that the petition, which was drawn up by the Italian-based Stop Vivisection European citizens’ initiative, could sway many newly elected MEPs who would then press the European commission into scrapping the directive which, in the UK, is enshrined in an amendment to the 1986 Animals (Scientific Procedures) Act. “Without the directive, research using animals would be blocked and that would have terrible consequences,” said Nancy Lee, senior policy adviser at the Wellcome Trust. “New medicines for Alzheimer’s, heart disease, cancer and other conditions could no longer be tested. Similarly, new drugs for animals would also be blocked.” This view is backed by Dame Kay Davies, director of the MRC functional genomics unit at Oxford University. “Removal of the directive would be a significant step backwards both for animal welfare in the EU and for Europe’s leading role in advancing human and animal health,” she said in last week’s Nature. Other citizens’ initiatives, which require a minimum of a million signatures before they are heard by the European parliament, have included calls for improved water supplies and stricter speed limits in Europe.
Keyword: Animal Rights
Link ID: 20905 - Posted: 05.11.2015
By Lena H. Sun Most babies in the United States are born on a weekday, with the highest percentages delivered between 8 a.m. to 9 a.m., and from noon to 1 p.m., according to a report published Friday by the National Center for Health Statistics. That won't come as too much of a surprise to many pregnant women who had cesarean deliveries. Most births in the United States take place in hospitals. And as C-sections and induced labor have increased during the past few decades, more deliveries take place during the day, to maximize coordination and care with doctors and hospital staff. But what happens if the baby isn't born in the hospital, but in the home, where most out-of-hospital births occur? (Less than 2 percent of all U.S. births take place outside the hospital.) Those births were most likely to take place in the wee morning hours between 1 a.m. and 4:59 a.m., the report found. The reason: mother nature. "Where nature is taking its course, infants are more likely to be born when it's completely dark out," said T.J. Mathews, a demographer with the National Center for Health Statistics, part of the U.S. Centers for Disease Control and Prevention. Researchers think evolution may have something to do with making the middle of the night an optimal time for delivery. Say you were pregnant and part of a nomadic tribe. Having your baby in the middle of the day could mean the rest of the tribe leaves you behind as they move from place to place. "You probably bled to death," said Aaron Caughey, chairman of the Department of Obstetrics and Gynecology at Oregon Health & Science University's School of Medicine.
Keyword: Biological Rhythms
Link ID: 20904 - Posted: 05.09.2015
by Bethany Brookshire Certain images conjure up intense emotion: crying children, a bloody face, a snake rearing for a strike. When people take in pictures that hold deep meaning for them, they actually see the images more vividly. For them, emotion gives the world an extra burst of Technicolor and increases the odds that they will remember the scene. But the amount of visual boost — called emotionally enhanced vividness — varies from person to person. Some of this variability is in our genes, a new study finds, suggesting that people really do see the world in different ways. Many of us are familiar with the chemical messenger norepinephrine as a stress chemical. But it doesn’t just dictate whether we fight or flee, says Rebecca Todd, a cognitive neuroscientist at the University of British Columbia in Vancouver. Norepinephrine is also very important for emotional memory. “It’s important in the initial perception of emotional stimuli,” she explains. “It weighs down emotional memories so they burn brighter.” Norepinephrine is produced in an area of the brain called the locus coeruleus. In an ideal system, the cells in this area produce norepinephrine in response to a signal such as stress. The norepinephrine signals pass to other areas of the brain, but some chemical messenger remains, binding to receptors called alpha2b adrenoreceptors on cells in the locus coeruleus. These adrenoreceptors act as a brake, stopping the production of norepinephrine before things get out of hand. The receptors are produced by the gene ADRA2b. But a substantial proportion of Europeans and Africans have a variation on ADRA2b that deletes the alpha2b adrenoreceptor, possibly cutting some of the wires on the norepinephrine brakes. People with this deletion had stronger memories of emotionally charged events, a 2007 study found. Todd and graduate student Mana Ehlers wanted to see if this deletion might affect how people perceived emotional images. © Society for Science & the Public 2000 - 2015.
By Lisa Sanders, M.D On Thursday we challenged Well readers to solve the difficult case of twin sisters who, in the prime of youth, developed a weakness that forced them to use their arms to rise from a chair. Nearly 300 of you wrote in with thoughts on this difficult case. Many of you recognized that this was likely to be a genetic disorder, though I greatly admired the “House”-ian thinking that led to a host of possible reasons why two sisters, living in different states, might develop the same symptoms independent of their shared DNA. It took this patient, Katie Buryk, four years to get her answer, which was: Late onset Tay-Sachs disease Although several of you made this difficult diagnosis, the first to do so was George Bonadurer, a second year medical student at Mayo Medical School in Rochester, Minn. He says he recently read about this disease in a book of unusual cases that had come to the Mayo clinic for help. This is actually Mr. Bonadurer’s second win of this contest. Strong work! Tay-Sachs disease was first identified by two physicians, independently, in the 1880s. Dr. Warren Tay was an ophthalmologist in London. Dr. Bernard Sachs was a neurologist in New York City. Each described a disease in infants that caused profound weakness, blindness and, usually by age 4, death. Careful consideration of cases over the following decades showed that the disease was inherited and often seen in children of Ashkenazi descent. Studying the patterns of inheritance, it became clear that both parents had to have the abnormal gene and that each of their children would have a one in four chance of being born with the disease. The terrible manifestations of the disease derive from an inherited inability to make an essential protein in the brain. This protein acts to break down discarded components of the cells. Without this protein, these discarded cell parts accumulate, interrupting normal nerve and brain cell functioning. This mechanism and the missing protein was identified in 1969, allowing for the development of a test for carriers. Since the development of this test, the incidence of Tay-Sachs in the United States has dropped by 90 percent. © 2015 The New York Times Company
By Chris Cesare For bats, too many echoes can be like blurry vision. That’s because the nocturnal creatures navigate by bouncing ultrasonic sound off of their surroundings, a technique known as echolocation. In cramped spots, these sounds can reverberate, creating a noisy background that clouds the mammals’ sonic sight. Now, new research published online before print in the Proceedings of the National Academy of Sciences has discovered one way that bats might overcome this auditory ambush. Scientists found that the animals modify the width of their navigation pulses on the fly by adjusting the size of their mouth gape. The researchers used an array of cameras, flashes, and ultrasonic recorders to take snapshots of bats while they swooped down to take a sip at a desert pond in Israel. As the bats descended toward the confined banks of the pond, they opened their mouths wider to more tightly focus their sound pulses. As the bats left, they narrowed their mouths, projecting an ultrasonic beam up to four times wider than on the descending leg. These counterintuitive effects were due to diffraction, which causes sound waves traveling through a smaller hole to spread out more. The researchers repeated the experiment with captive bats and found the same effect, controlling for the possibility that they had observed a behavior tied to drinking. The team writes that these changes in gape allow the animals to “zoom in” on their view of an area, potentially reducing the amount of distracting echoes in a tight space. © 2015 American Association for the Advancement of Science
Link ID: 20901 - Posted: 05.09.2015
by Clare Wilson IT IS considered a soft drug, but increasing numbers of people are seeking help for cannabis addiction – and there's growing interest in finding ways to treat them. Paradoxically, the most promising treatment may be an extract of cannabis. Last month, researchers at the British Neuroscience Association meeting in Edinburgh, UK, described how the compound, called cannabidiol, helped one person who was severely addicted. A clinical trial is underway. Unlike most forms of drug addiction, there are no medical treatments to help people reduce their cannabis use. "Cannabis dependence is a huge unmet need with no pharmacological treatments," says Tom Freeman of University College London, who is involved in the trial. "It's vital we get one." A possible connection between smoking pot and schizophrenia is fairly well known, but the link is controversial and it affects only a small minority of users. Addiction seems to be a more common problem – yet is often overlooked. There is no universal definition of addiction or dependence. Someone is usually deemed to be addicted to a drug if they want to stop but cannot, or if it has a negative impact on their life. They would probably be experiencing withdrawal symptoms that make it hard to give up. In the case of heavy cannabis use, these can include anxiety and insomnia.
Keyword: Drug Abuse
Link ID: 20900 - Posted: 05.08.2015
By Rachel Feltman Animals didn't always have heads. We know that sometime during the Cambrian Period -- around 500 million years ago, as animals transitioned from the squishy likes of the penis worm to hard-bodied arthropods -- body segments started transitioning into something like the head/body differentiation we see today. But figuring out just how that transition went can be tricky. A study published on Thursday in Current Biology looks to one of the oldest-ever brain fossils for clues. Brains, being all squishy and stuff, aren't commonly found in fossilized form, especially not 500 million years after the fact. But the new study compares two specimens: A trilobite with a squishy body and Odaraia alata, a creature said to resemble a submarine. Cute, yeah? The Cambrian was such a great time. Lead author Javier Ortega-Hernández, a postdoctoral researcher from Cambridge's Department of Earth Sciences, found that the front portions of both creatures' brains had nerve connections to their eye stalks and a hard plate called the anterior sclerite. In modern arthropods, that brain region controls the eyes. Ortega-Hernández believes that this anterior sclerite was a bridge between ancient arthropods and more modern ones. Anomalocaridids, which lived at the same time but looked very different, have a plate that Ortega-Hernández thinks came from the same ancestral anatomy that went on to form anterior sclerites in the animals he examined (and, eventually, a more modern head structure today).
Link ID: 20899 - Posted: 05.08.2015
by Clare Wilson WHAT is it like to be a bat? It's a question philosophers interested in consciousness like to ponder. Yet a few people already have something of a bat's world view. Brian Borowski, a 59-year-old Canadian who was born blind, began teaching himself to echolocate aged 3. He clicks with his tongue or snaps his fingers as he moves about, unconsciously decoding the echoes. Although many blind people get information from sounds around them, few turn this into a supersense by making sounds to help themselves get around. "When I'm walking down a sidewalk and I pass trees, I can hear the tree: the vertical trunk of the tree and maybe the branches above me," says Borowski. "I can hear a person in front of me and go around them." Borowski, who works as a programmer at Western University in London, Ontario, suspects he experiences "images" in a similar way to people who can see, just with less detail. "I store maps of information in my head and I compare what I have in my memory with what I'm hearing around me," he says. "I am matching images of some sort." This probably isn't too far from the truth – we know from brain scans of Borowski and another echolocator that the strategy co-opts the same parts of the brain that usually deal with visual information. For his latest scientific collaboration, he helped a team of researchers to explore how well echolocators can determine the relative sizes and distances of objects. © Copyright Reed Business Information Ltd
Link ID: 20898 - Posted: 05.08.2015
Andrew Griffin Companies are taking out a huge amount of patents related to reading brainwaves, according to analysis, with a range of different applications. Fewer than 400 neuro-technology related patents were filed between 2000-2009. But in 2010 alone that reached 800, and last year 1,600 were filed, according to research company SharpBrains. The patents are for a range of uses, not just for the healthcare technology that might be expected. The company with the most patents is market research firm Nielsen, which has 100. Microsoft also has 89 related patents. Other uses of the technology that have been patented include devices that can change the thoughts of feelings of those that they are used on. But there are still medical uses — some of those patents awarded include technology to measure brain lesions and improve vision. The volume and diversity of the patents shows that we are at the beginning of “the pervasive neurotechnology age”, the company’s CEO Alvaro Fernandez said. "Neurotech has gone well beyond medicine, with non-medical corporations, often under the radar, developing neurotechnologies to enhance work and life," said Fernandez.
By Melissa Healy contact the reporter Schizophrenia is one of psychiatry's most puzzling afflictions, with a complex of symptoms that goes far beyond its hallmark hallucinations and delusional thinking. But new research has found connections among several of schizophrenia's peculiar collection of symptoms -- including agitation and memory problems -- and linked them to a single genetic variant among the hundreds thought to heighten risk of the disorder. The findings offer new insights into the molecular basis for schizophrenia and could lead to treatments for the disease that are more targeted and more comprehensive. Published Monday in the journal Nature Neuroscience, the study looks at how a gene variant called Arp2/3 contributes to psychosis, agitation and problems of short- and long-term memory. Mice that were genetically modified to lack the Arp2/3 gene variant showed all three symptoms (although to measure psychosis in mice, scientists looked instead for an abnormal startle response that is also seen in humans in the grips of psychosis). The study's authors, led by Duke University neurobiologist Scott Soderling, then dug below those behaviors to see whether brain abnormalities linked to such behaviors had anything in common. Mice that lacked the Arp2/3 gene variant, they discovered, had not only symptoms of schizophrenia, but also several of the underlying brain abnormalities most closely linked to psychosis, agitation and memory problems seen in those with schizophrenia.
Link ID: 20895 - Posted: 05.06.2015
Douwe Draaisma When we sleep, wrote English psychiatrist Havelock Ellis over a hundred years ago, we enter a ‘dim and ancient house of shadow’. We wander through its rooms, climb staircases, linger on a landing. Towards morning we leave the house again. In the doorway we look over our shoulders briefly and with the morning light flooding in we can still catch a glimpse of the rooms where we spent the night. Then the door closes behind us and a few hours later even those fragmentary memories we had when we woke have been wiped away. That is how it feels. You wake up and still have access to bits of the dream. But as you try to bring the dream more clearly to mind, you notice that even those few fragments are already starting to fade. Sometimes there is even less. On waking you are unable to shake off the impression that you have been dreaming; the mood of the dream is still there, but you no longer know what it was about. Sometimes you are unable to remember anything at all in the morning, not a dream, not a feeling, but later in the day you experience something that causes a fragment of the apparently forgotten dream to pop into your mind. No matter what we may see as we look back through the doorway, most of our dreams slip away and the obvious question is: why? Why is it so hard to hold on to dreams? Why do we have such a poor memory for them? In 1893, American psychologist Mary Calkins published her ‘Statistics of Dreams’, a numerical analysis of what she and her husband dreamed about over a period of roughly six weeks. They both kept candles, matches, pencil and paper in readiness on the bedside table. But dreams are so fleeting, Calkins wrote, that even reaching out for matches was enough to make them disappear. Still with an arm outstretched, she was forced to conclude that the dream had gone. © 2015 Salon Media Group, Inc
by Laura Sanders On a test of visual perception, children with autism perceive moving dots with more clarity than children without the disorder. The results, published in the May 6 Journal of Neuroscience, reveal a way in which children with autism see the world differently. When asked to determine the overall direction of a mess of dots moving in slightly different directions, children with autism outperformed children without the disorder. Other tests of motion detection didn’t turn up any differences. The results suggest that children with autism may be taking in and combining more motion information than children without autism, says study coauthor Catherine Manning of the University of Oxford. This heightened ability may contribute to feelings of sensory overload, the researchers suggest. © Society for Science & the Public 2000 - 2015
By Jocelyn Kaiser One of the most heralded successes of gene therapy may not be the permanent fix that many had hoped. Leaders of two clinical trials report this week that a treatment that restored some vision to blind patients begins to fade within a few years. A third group, however, says their patients, who received a different version of the therapy, are retaining their improved vision, and a company is moving ahead with efforts to gain regulatory approval for their treatment. It is not a huge surprise that the treatment effects may not last, says eye disease researcher Mark Pennesi of Oregon Health & Science University in Portland, who is running a similar trial. “These are complex diseases and everything that’s been done is sort of first generation,” he says. “The fact that there was biological activity at all is a milestone.” At issue is gene therapy for a rare form of inherited blindness known as Leber’s congenital amaurosis (LCA) that results in complete vision loss by about age 40. About 10% of cases are due to a mutation in retinal pigment epithelium 65 (RPE65), a gene that codes for an enzyme that helps retinal cells make rhodopsin. The pigment is needed by photoreceptor cells—the retina’s light-sending rods and cones—and when RPE65 is mutated, the photoreceptor cells gradually die. In 2007, in the first-ever effort to use gene therapy to treat people with blindness, three separate teams in the United States and the United Kingdom launched clinical trials for the RPE65 type of LCA. A surgeon injected one eye of each patient with a solution containing a harmless virus that ferried a good copy of RPE65 into retinal cells. © 2015 American Association for the Advancement of Science
Link ID: 20892 - Posted: 05.05.2015