By Karen Rowan and MyHealthNewsDaily Children at an increased risk of autism may have abnormal structures in the placenta that can be detected at birth, a new study finds. The findings suggest behavioral interventions aimed at social and motor skill development in these children could be started right away, the researchers said. Studies have shown that such interventions are more effective in children with autism when they are started earlier. It's much too early to say that an examination of the placenta could be used as a definitive test for autism at birth, said study researcher Dr. Harvey Kliman, director of Reproductive and Placental Research at the Yale University School of Medicine. Autism spectrum disorders are typically diagnosed when children are ages 3 or 4, or even older. However, if these structures were found upon a child's birth and interventions were started, the child might benefit greatly if they did turn out to have autism, while there would be little downside if a child turned out not to have autism -- it's unlikely they would be harmed by the effort, Kliman said. In the study, Kliman and his colleagues collected samples of placenta tissue from 117 children born to families who already had a child with autism, and compared them with placentas from 100 babies born into families in which no older children had autism. The researchers, who didn't know which placentas had come from each group of children, examined samples of the placentas under microscopes. © 2013 Scientific American

Keyword: Autism; Aggression
Link ID: 18080 - Posted: 04.27.2013

By KATIE THOMAS With the diagnosis of autism on the rise and drug companies facing major setbacks in developing successful treatments, the University of California, Los Angeles will lead a $9 million effort financed by the National Institute of Mental Health to find effective drugs, officials said Wednesday. Under a contract with the institute, U.C.L.A. will form a network of researchers at other academic centers that will try to identify promising new and older drug compounds quickly, and conduct early tests to see if they merit additional investment. The program, part of the “Fast Fail” initiative at the institute, aims to determine within weeks whether a drug works, rather than the years it traditionally takes to evaluate a new drug. “The whole idea is just getting much better in these early phases at identifying drugs that are going to be efficacious and safe, and thereby greatly speeding the development of effective new therapies and reducing the overall cost,” said Dr. James McCracken, who is leading the effort at U.C.L.A. as director of the division of child and adolescent psychiatry at the Semel Institute for Neuroscience and Human Behavior. The number of diagnosed cases of autism, Asperger’s syndrome and related disorders in children has been growing in recent years, largely because of increased awareness. A recent report by the Centers for Disease Control and Prevention and the Health Resources and Services Administration concluded that one in 50 children aged 6 to 17 had been found to have autism or a related disorder, a 72 percent increase since 2007. Although more cases are being diagnosed, no drugs are approved to treat the core symptoms of the disorders, which are characterized by delays in developing effective communication and social skills. Other drugs often prescribed to people with the disorders treat difficult behaviors like aggressiveness, hyperactivity and irritability. © 2013 The New York Times Company

Keyword: Autism
Link ID: 18070 - Posted: 04.25.2013

By PAM BELLUCK After most pregnancies, the placenta is thrown out, having done its job of nourishing and supporting the developing baby. But a new study raises the possibility that analyzing the placenta after birth may provide clues to a child’s risk for developing autism. The study, which analyzed placentas from 217 births, found that in families at high genetic risk for having an autistic child, placentas were significantly more likely to have abnormal folds and creases. “It’s quite stark,” said Dr. Cheryl K. Walker, an obstetrician-gynecologist at the Mind Institute at the University of California, Davis, and a co-author of the study, published in the journal Biological Psychiatry. “Placentas from babies at risk for autism, clearly there’s something quite different about them.” Researchers will not know until at least next year how many of the children, who are between 2 and 5, whose placentas were studied will be found to have autism. Experts said, however, that if researchers find that children with autism had more placental folds, called trophoblast inclusions, visible after birth, the condition could become an early indicator or biomarker for babies at high risk for the disorder. “It would be really exciting to have a real biomarker and especially one that you can get at birth,” said Dr. Tara Wenger, a researcher at the Center for Autism Research at Children’s Hospital of Philadelphia, who was not involved in the study. © 2013 The New York Times Company

Keyword: Autism; Aggression
Link ID: 18069 - Posted: 04.25.2013

By KJ DELL'ANTONIA A cautiously worded study based on data collected in Sweden has found that “in utero exposure to both selective serotonin reuptake inhibitors (S.S.R.I.’s) and nonselective monoamine reuptake inhibitors (tricyclic antidepressants) was associated with an increased risk of autism spectrum disorders, particularly without intellectual disability.” The Swedish medical birth register (which contains data on current drug use reported by mothers early in their pregnancies), along with a system of publicly funded screenings for autism spectrum disorders and extensive national and regional registers of various health issues, make a detailed, population-based case-control study possible — one that controls for other variables like family income, parent educational level, maternal and paternal age and even maternal region of birth (all factors the authors note have been previously associated with autism). This is the second study in two years to associate antidepressant use during pregnancy with an increased incidence of autism in exposed children. An earlier, smaller study in California also found a modest increase in risk. The Sweden-based study could not (and did not) exclude the possibility that it was the severe depression, rather than the use of antidepressants, that created the association, but the smaller California study (which considered only S.S.R.I.’s) found “no increase in risk” for mothers with a history of mental health treatment in the absence of prenatal exposure to S.S.R.I.’s. © 2013 The New York Times Company

Keyword: Autism; Aggression
Link ID: 18064 - Posted: 04.23.2013

By GREGORY COWLES When John Elder Robison was teaching his young son, Cubby, the finer points of etiquette almost two decades ago, he noted that in addition to “please” and “thank you,” it’s nice to include a salutation while making a request. “For example,” he said, “if you wanted me to get you milk, you could say: ‘Please, wondrous Dada, may I have some milk?’ ” The salutation never caught with Cubby. But by the last page of Mr. Robison’s engaging new memoir, readers may have no problem hailing the author that way. Part parenting guide, part courtroom drama, part catalog of the travails and surprising joys of life with the high-functioning form of autism called Asperger’s syndrome, this memoir will offer all parents — but particularly fathers — a lot to think about. That its author was almost 40 when he learned he had Asperger’s (a discovery he described in his first memoir, “Look Me in the Eye”), and that he eventually learned his son had the condition as well, make their story more remarkable, but do nothing to diminish its relevance even for readers with no personal experience of autism. Indeed, it can be hard to pinpoint what in the Robisons’ relationship is shaped by Asperger’s and what stems from their own idiosyncratic personalities. Cubby’s name, for instance: Mr. Robison tells us that when his wife (now ex) was pregnant, “I sensed that the best names were not in books at all. For example, if we ended up with a girl, I favored naming her Thugwena, because I knew a girl named Thugwena would be tough and not hassled by bullies.” For boys he liked Thugwald, or else “functional choices” like Kid or Boy. Is this an example of his deadpan humor, in evidence throughout, or is it his Asperger’s blinding him to how others might perceive his actions? Just when you conclude that his tongue is firmly in his cheek, he drops a passing reference to the family cat, Small Animal. © 2013 The New York Times Company

Keyword: Autism
Link ID: 18063 - Posted: 04.23.2013

By Michelle Roberts Health editor, BBC News online Canadian doctors say they have found an inventive way to treat lazy eye - playing the Tetris video game. The McGill University team discovered the popular tile-matching puzzle could train both eyes to work together. In a small study, in Current Biology with 18 adults, it worked better than conventional patching of the good eye to make the weak one work harder. The researchers now want to test if it would be a good way to treat children with the same condition. UK studies are already under way. An estimated one in 50 children has lazy eye, known medically as amblyopia. It happens when the vision in one eye does not develop properly, and is often accompanied by a squint - where the eyes do not look in the same direction. Without treatment it can lead to a permanent loss of vision in the weak eye, which is why doctors try to intervene early. Normally, the treatment is to cover the strong eye with a patch so that the child is forced to use their lazy eye. The child must wear the patch for much of the day over many months, which can be frustrating and unpleasant. BBC © 2013

Keyword: Vision; Aggression
Link ID: 18062 - Posted: 04.23.2013

By ABBY ELLIN Marvin Tolkin was 83 when he decided that the unexamined life wasn’t worth living. Until then, it had never occurred to him that there might be emotional “issues” he wanted to explore with a counselor. “I don’t think I ever needed therapy,” said Mr. Tolkin, a retired manufacturer of women’s undergarments who lives in Manhattan and Hewlett Harbor, N.Y. Though he wasn’t clinically depressed, Mr. Tolkin did suffer from migraines and “struggled through a lot of things in my life” — the demise of a long-term business partnership, the sudden death of his first wife 18 years ago. He worried about his children and grandchildren, and his relationship with his current wife, Carole. “When I hit my 80s I thought, ‘The hell with this.’ I don’t know how long I’m going to live, I want to make it easier,” said Mr. Tolkin, now 86. “Everybody needs help, and everybody makes mistakes. I needed to reach outside my own capabilities.” So Mr. Tolkin began seeing Dr. Robert C. Abrams, a professor of clinical psychiatry at Weill Cornell Medical College in Manhattan. They meet once a month for 45 minutes, exploring the problems that were weighing on Mr. Tolkin. “Dr. Abrams is giving me a perspective that I didn’t think about,” he said. “It’s been making the transition of living at this age in relation to my family very doable and very livable.” Mr. Tolkin is one of many seniors who are seeking psychological help late in life. Most never set foot near an analyst’s couch in their younger years. But now, as people are living longer, and the stigma of psychological counseling has diminished, they are recognizing that their golden years might be easier if they alleviate the problems they have been carrying around for decades. It also helps that Medicare pays for psychiatric assessments and therapy. Copyright 2013 The New York Times Company

Keyword: Development of the Brain; Aggression
Link ID: 18061 - Posted: 04.23.2013

By Kate Wong Odds are you carry DNA from a Neandertal, Denisovan or some other archaic human. Just a few years ago such a statement would have been virtually unthinkable. For decades evidence from genetics seemed to support the theory that anatomically modern humans arose as a new species in a single locale in Africa and subsequently spread out from there, replacing archaic humans throughout the Old World without mating with them. But in recent years geneticists have determined that, contrary to that conventional view, anatomically modern Homo sapiens did in fact interbreed with archaic humans, and that their DNA persists in people today. In the May issue of Scientific American, Michael Hammer of the University of Arizona in Tucson examines the latest genetic findings and explores the possibility that DNA from these extinct relatives helped H. sapiens become the wildly successful species it is today. As Scientific American’s anthropology editor, I have an enduring interest in the rise of H. sapiens; and as longtime readers of this blog may know, I’m fascinated (you might even say obsessed) with Neandertals. So naturally I’ve been keen to find out how much, if any, Neandertal DNA I have in my own genome. Several consumer genetic testing companies now test for Neandertal genetic markers as part of their broader ancestry analysis, and after 23andMe lowered the price of their kit to $99 in December, I decided to take the plunge. As it happens, National Geographic’s Genographic Project had recently updated their own genetic test to look for Neandertal DNA, and they sent me a kit (retail price: $299) for editorial review, much as publishers do with new books. And so it was on a chilly Saturday in late January that I found myself spitting into a test tube for 23andMe and swabbing my cheek for the Genographic Project. © 2013 Scientific American

Keyword: Evolution; Aggression
Link ID: 18057 - Posted: 04.23.2013

By Emily Chung, CBC News Having a stressed-out mom may give baby squirrels a competitive edge, a new study suggests. Red squirrels who were stressed out during pregnancy had babies that out-competed their peers by growing significantly faster without any extra food, reported the study, published online in Science Express. "What that suggests is that they're first able to predict what sort of environment their offspring will encounter… and they're preparing them for what their offspring are going to face," said Ben Dantzer, lead author of the study he worked on while he was a Ph.D. student at Michigan State University under the supervision of Guelph University biologist Andrew McAdam. Further investigation uncovered a link between faster growth among the baby squirrels and higher levels of stress hormones in their mothers during the pregnancies. That link may explain how environmental conditions cue the animals to respond and adapt. Canadian researchers, including Stan Boutin at the University of Alberta, Murray Humphreys at McGill University in Montreal and McAdam at the University of Guelph, had been studying red squirrels near Kluane Lake, Yukon, for 22 years to find out how they are affected by changes in resources such as food over time. © CBC 2013

Keyword: Stress; Aggression
Link ID: 18049 - Posted: 04.20.2013

by Dennis Normile A human mother rocking a baby in her arms and a cat carrying her kitten by the scruff of its neck have the same physiological effect on both young animals and probably stem from the same maternal instinct to protect their young. That's the conclusion of a new study, which for the first time has compared the physiological impact of maternal carrying behaviors across species. The findings may lead to better parenting techniques for people and possibly to new ways to detect developmental disorders early in life. It's "really fascinating" work, says Oliver Bosch, a neurobiologist at the University of Regensburg in Germany, who was not involved in the research. "No one has looked at [this aspect] of maternal behavior in such detail." Japanese neuroscientist Kumi Kuroda began the study in her own home. She noticed that carrying her newborn baby boy while walking had a rapid calming effect on him. Back in her lab at the RIKEN Brain Science Institute, near Tokyo, she found that picking up mouse pups by the scruff of the neck makes them passive and easy to handle. Kuroda wondered if the same physiological processes were driving both behaviors. She and colleagues recorded pulse rates and observed the crying and squirming behavior of 12 infants, 1 to 6 months old, as each was left alone in a crib, held by its mother sitting in a chair, and carried as the mother walked around. In various durations and combinations of the three conditions, they found that the carried babies cried and squirmed the least and had the lowest pulse rates. Those left in the crib were the fussiest; holding the baby while sitting produced in-between results. What was particularly surprising, Kuroda says, was that when a mother started walking, the infant's pulse dropped, and the crying and squirming stopped within 2 to 3 seconds, not over several minutes. © 2010 American Association for the Advancement of Science.

Keyword: Development of the Brain; Aggression
Link ID: 18048 - Posted: 04.20.2013

by Douglas Heaven A glimpse of consciousness emerging in the brains of babies has been recorded for the first time. Insights gleaned from the work may aid the monitoring of babies under anaesthesia, and give a better understanding of awareness in people in vegetative states – and possibly even in animals. The human brain develops dramatically in a baby's first year, transforming the baby from being unaware to being fully engaged with its surroundings. To capture this change, Sid Kouider at the Ecole Normale Supérieure in Paris, France, and colleagues used electroencephalography (EEG) to record electrical activity in the brains of 80 infants while they were briefly shown pictures of faces. In adults, awareness of a stimulus is known to be linked to a two-stage pattern of brain activity. Immediately after a visual stimulus is presented, areas of the visual cortex fire. About 300 milliseconds later other areas light up, including the prefrontal cortex, which deals with higher-level cognition. Conscious awareness kicks in only after the second stage of neural activity reaches a specific threshold. "It's an all-or-nothing response," says Kouider. Adults can verbally describe being aware of a stimulus, but a baby is a closed book. "We have learned a lot about consciousness in people who can talk about it, but very little in those who cannot," says Tristan Bekinschtein at the University of Cambridge, who was not involved in the work. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Aggression
Link ID: 18047 - Posted: 04.20.2013

by Simon Makin The first drug specifically designed to improve cognitive impairment in Down's syndrome is being tested in humans. David Nutt, former drug policy adviser to the UK government, told delegates at the Festival of Neuroscience in London yesterday that he is collaborating with pharmaceutical company Roche in trials of a substance it developed, called RG1662. RG1662 reverses the effects of a chemical messenger in the brain called GABA – a neurotransmitter that inhibits brain activity. The drug acts on a specific type of brain receptor found mostly in the hippocampus, a part of the brain involved in memory. It is thought that it will reduce excessive inhibition in the hippocampus, thought to underlie memory and learning problems commonly seen in people with Down's. The study is currently assessing safety and tolerability of the drug in 33 adults with Down's, but researchers will also measure motor skills, reaction time and memory, and compare the results with those of people taking a placebo. The aim is to find appropriate doses to use in a full clinical trial, which Nutt says should happen this year. Roche said in a statement that RG1662 may help people with Down's as it has "a unique pharmacology that enables the targeting of GABA over-activity mainly in brain systems important for cognition, learning and memory". © Copyright Reed Business Information Ltd

Keyword: Learning & Memory
Link ID: 18026 - Posted: 04.13.2013

by Elizabeth Norton A loving gaze helps firm up the bond between parent and child, building social skills that last a lifetime. But what happens when mom is blind? A new study shows that the children of sightless mothers develop healthy communication skills and can even outstrip the children of parents with normal vision. Eye contact is one of the most important aspects of communication, according to Atsushi Senju, a developmental cognitive neuroscientist at Birkbeck, University of London. Autistic people don't naturally make eye contact, however, and they can become anxious when urged to do so. Children for whom face-to-face contact is drastically reduced—babies severely neglected in orphanages or children who are born blind—are more likely to have traits of autism, such as the inability to form attachments, hyperactivity, and cognitive impairment. To determine whether eye contact is essential for developing normal communication skills, Senju and colleagues chose a less extreme example: babies whose primary caregivers (their mothers) were blind. These children had other forms of loving interaction, such as touching and talking. But the mothers were unable to follow the babies' gaze or teach the babies to follow theirs, which normally helps children learn the importance of the eyes in communication. Apparently, the children don't need the help. Senju and colleagues studied five babies born to blind mothers, checking the children's proficiency at 6 to 10 months, 12 to 15 months, and 24 to 47 months on several measures of age-appropriate communications skills. At the first two visits, babies watched videos in which a woman shifted her gaze or moved different parts of her face while corresponding changes in the baby's face were recorded. Babies also followed the gaze of a woman sitting at a table and looking at various objects. © 2010 American Association for the Advancement of Science

Keyword: Development of the Brain; Aggression
Link ID: 18023 - Posted: 04.11.2013

A rat with some human genes could provide a better way to test Alzheimer's drugs. The genetically modified rat is the first rodent model to exhibit the full range of brain changes found in Alzheimer's, researchers in The Journal of Neuroscience. "It's a big step forward" for drug development, says , a program director at the National Institute of Neurological Disorders and Stroke, or NINDS, which helped fund the work. "The closer the model is to the human condition in representing the disease, the more likely the drug will behave and cure the way it would in humans." In recent years, drug companies have developed several Alzheimer's drugs that seemed to work in animals, but with the disease. A lack of good animal models for Alzheimer's may be one reason for those failures, researchers say. For the past couple of decades, Alzheimer's researchers have relied primarily on mice that carry human gene mutations that cause people to get the disease in their 40s or 50s. Like people, these mice develop so-called amyloid plaques in their brains. But that's where the similarity ends. In people with Alzheimer's, after plaques appear, huge numbers of brain cells die. That's never happened in mice, despite lots of genetic tinkering, Corriveau says. So researchers began to consider a different rodent model: the rat. "Rats are 4 [million] to 5 million years closer evolutionarily to humans," Corriveau says, which means their brains are more like ours. ©2013 NPR

Keyword: Alzheimers; Aggression
Link ID: 18016 - Posted: 04.11.2013

By PAULA SPAN The long list of roles Margaret Thatcher played during her 87 years — potent politician, free-market evangelist, labor antagonist, dominant global leader — includes the one she never publicly discussed: person with dementia. The stroke that killed her on Monday was not her first. Mrs. Thatcher suffered several small strokes more than a decade earlier, canceled all her speaking engagements in 2003 and largely withdrew from public life. Even before the strokes, her daughter, Carol, wrote in a 2008 memoir, she was losing cognitive ground, repeating questions and showing other signs of confusion. Heartbreakingly, she often forgot that her beloved husband, Denis, had died of cancer in 2003. “I had to keep giving her the bad news over and over again,” her daughter wrote. “Every time it finally sank in that she had lost her husband of more than 50 years, she’d look at me sadly and say, ‘Oh’, as I struggled to compose myself. ‘Were we all there?’ she’d ask softly.” At the time, members of her mother’s political circle and other British commentators denounced Carol Thatcher for invading her mother’s privacy and, supposedly, diminishing her dignity. The criticism arose again in some quarters last year, when Meryl Streep won an Oscar for her portrayal of Mrs. Thatcher’s dementia in “The Iron Lady.” © 2013 The New York Times Company

Keyword: Alzheimers
Link ID: 18012 - Posted: 04.10.2013

By Janice Lynch Schuster, My grandmother, who is 92, recently reported that she’d seen three giraffes in her Midwest back yard. She is otherwise sharp (and also kind and funny), but the giraffe episode was further evidence of the mild cognitive impairment that has been slowly creeping into her life. The question for my family has become: How should we respond? One of my sisters tried humor. (“Grandmom, I didn’t know you drank in the middle of the day!”) My father suggested that they were deer (to which she replied, “I’m 92 years old, and I know a giraffe when I see one.”) I tried to learn more about what, exactly, the giraffes were doing out there. (She didn’t seem to know, saying only that “the light shimmered.”) Communicating with a family member who has cognitive impairment can be frustrating and disheartening, even downright depressing for patient and caregiver alike. And it’s a problem faced by a growing number of Americans. According to a report published last week, about 4.1 million Americans have dementia. Alzheimer’s, one of the many forms of dementia, is the most expensive disease in the United States, costing $157 billion to $215 billion a year — more than heart disease and cancer, according to the study, which was sponsored by the National Institute on Aging. As baby boomers reach old age, these numbers are expected to increase dramatically. A number of techniques can not only reduce the frustration but also create new ways of connecting. Among the most effective and popular among experts is the “validation method,” a practice pioneered by geriatric social worker and researcher Naomi Feil in the 1980s. © 1996-2013 The Washington Post

Keyword: Alzheimers; Aggression
Link ID: 18011 - Posted: 04.10.2013

by Dr. Tyeese Gaines African-Americans with a particular gene are twice as likely to develop Alzheimer’s disease in old age as those without it, says a new study published in the Journal of the American Medical Association. This finding is a result of the largest database search for Alzheimer’s genes among African-Americans. “Until now, data on the genetics of Alzheimer’s in this patient population have been extremely limited,” said Dr. Richard Mayeux, chair of neurology at Columbia University Medical Center and senior author of the study. Alzheimer’s disease is the most common cause of dementia — a brain disease that affects memory, personality and the ability to reason. At age 65, only one percent of people have Alzheimer’s, yet over 80 years of age, it increases to 30 percent. A gene called APOE is associated with one in every five cases of Alzheimer’s – known to be a major genetic risk factor for whites and blacks. Yet, in this new research, Mayeux and his team identified an additional gene variant linked to a doubled risk in African-Americans alone, called ABCA7. “ABCA7 is the first major gene implicated in late-onset Alzheimer’s among African-Americans,” said Dr. Christine Reitz, assistant professor of neurology and lead author of the study. To reach this conclusion, researchers examined samples from nearly 6,000 African-American men and women collected between 1989 and 2011 – 2,000 had a diagnosis of probable Alzheimer’s disease and the other 4,000 had no cognitive difficulty. “Although this is a very significant finding, it does not change much for the everyday African-American male or female,” says Rick Kittles, PhD, a human genetics expert who has traced the ancestry of more than 100,000 African-Americans. “There is still much work to do [to] determine how exactly this gene plays a role in Alzheimer’s disease.” ©2013 NBCUniversal

Keyword: Alzheimers; Aggression
Link ID: 18010 - Posted: 04.10.2013

By DENISE GRADY SAN FRANCISCO — Scientists are trained to be skeptics, and Elizabeth H. Blackburn considers herself one of the biggest. Show her the data, and be ready to defend it. But even though she relishes the give and take, Dr. Blackburn admits to impatience at times with the questions some scientists have raised about one of her ventures. “It’s just such a no-brainer, and yet people have such difficulty understanding it,” she said. At issue is a lab test that measures telomeres, stretches of DNA that cap the ends of chromosomes and help keep cells from aging too soon. Unusually short telomeres may be a sign of illness, and Dr. Blackburn, who shared the 2009 Nobel Prize in medicine for her work on telomeres (TEEL-o-meers), thinks measuring them could give doctors and patients a chance to intervene early and maybe even prevent disease. A company she helped found expects to begin offering tests to the public later this year. Other researchers have raised doubts about the usefulness of the measurement, which does not diagnose a specific disease. But Dr. Blackburn, 64, a professor of biology and physiology at the University of California, San Francisco, says she has been convinced by a decade of data from her own team and others, linking short telomeres to heart disease, diabetes, cancer and other diseases, and to chronic stress and post-traumatic stress disorder. With studies that explore the connections among emotional stress, health and telomeres, she has delved into questions that she would have shied away from earlier in her career, as a woman trying to establish herself in science. But now, she has enough confidence and autonomy to follow the leads that intrigue her. The scope of her research has expanded tremendously, from a tight focus on molecular biology to broader questions about the implications of her work for health and public policy. © 2013 The New York Times Company

Keyword: Stress; Aggression
Link ID: 18005 - Posted: 04.09.2013

By DOUGLAS QUENQUA The French geneticist Jérôme Lejeune discovered more than 50 years ago that Down syndrome is caused by the presence of an extra copy of chromosome 21. But to this day it has remained a mystery why that results in impaired physical and cognitive development. Now researchers at the Sanford-Burnham Medical Research Institute think they have found a clue. The scientists, who were investigating Alzheimer’s disease, found that mice that lacked a protein known as SNX27 had many of the same learning and memory defects as mice with Down syndrome. Looking at the brains of people with the syndrome, the researchers discovered that they, too, lacked SNX27. While chromosome 21 is not directly involved in SNX27 production, it does encode a regulator — miR-155 — that inhibits production. According to the study, published in the journal Nature Medicine, levels of miR-155 in the brains of people with Down syndrome correlate almost exactly with the decrease in SNX27. “In the brain, SNX27 keeps certain receptors on the cell surface — receptors that are necessary for neurons to fire properly,” said the study’s senior author, Huaxi Xu, in a statement released by the institute. “So in Down syndrome, we believe lack of SNX27 is at least partly to blame for developmental and cognitive defects.” To test their findings, Dr. Xu’s team introduced more SNX27 to mice with Down syndrome. As they expected, the mice showed immediate improvements in cognitive function and behavior. Now the researchers are investigating molecules that might increase production of SNX27 in the human brain. © 2013 The New York Times Company

Keyword: Development of the Brain; Aggression
Link ID: 18002 - Posted: 04.09.2013

By Neuroskeptic Last year, there was quite a bit of excitement over a “Genetic Test To Predict Risk for Autism”. The test was revealed in a paper in Molecular Psychiatry, by Australian researchers Skafidas and colleagues. The claim was that a statistical classifier could spot patterns of genetic variation that differed between people with autism and healthy controls – with 70% accuracy. For a good discussion of the paper, including comments from the lead author, see here. However, a Letter to Molecular Psychiatry has just cast doubt on the whole thing. The authors write A classifier was recently reported to predict with 70% accuracy if an individual has an autism spectrum disorder using 237 single-nucleotide polymorphisms (SNPs). Biomarkers, genetic or otherwise, that would facilitate earlier autism spectrum disorder diagnosis are crucial; therefore, these results warrant careful scrutiny. So scrutinize it they do, and they find it wanting: In other words, the ‘autism’ genetic variants were indeed more common in the autism cases, compared to controls, but only because the cases and controls were from different places. The classifier worked, but it wasn’t detecting autism, it was detecting ancestry.

Keyword: Autism; Aggression
Link ID: 17996 - Posted: 04.08.2013