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Archive - May 2015

May 28th

Surprisingly, Gene Alleles That Increase Triglyceride Levels Are Associated with Protection Against Type-2 Diabetes; Elevated Triglyceride Levels Normally Considered Risk Factor

Elevated plasma triglyceride level is considered a risk factor for type-2 diabetes, but new findings suggest that a genetically-elevated triglyceride level is associated with protection against type-2 diabetes. Dr. Yann Klimentidis, an Assistant Professor at the Mel and Enid Zuckerman College of Public Health at the University of Arizona, and colleagues found that triglyceride-increasing alleles are associated with decreased type-2 diabetes incidence. The team’s findings were published online on May 28, 2015 in the open-access journal PLOS Genetics. The title of the article is “Triglyceride-Increasing Alleles Associated with Protection Against Type-2 Diabetes.” Building on previous studies that hinted at the same association, Dr. Klimentidis and colleagues tested the relationship of triglyceride-associated genetic variants, collectively and individually, with type-2 diabetes incidence across three prospective cohort studies comprised of European- and African-American participants. Their findings across studies, racial groups, and statistical models consistently demonstrate that triglyceride-increasing alleles are associated with decreased type-2 diabetes incidence. The studied genes therefore appear to both increase triglyceride levels and decrease type-2 diabetes risk. Although no single gene appeared to be driving this trend, several, including a variant near the APOA1 gene, stood out as potentially interesting in relation to this finding. Although more work is needed to fully understand the physiological mechanisms that underlie these genetic associations and to further elucidate the causal relationship between triglycerides and type-2 diabetes, these findings are a promising start to our understanding of triglyceride-associated genes and their relationship with type-2 diabetes.

Zone in with Zon: First-Ever Lab Test to Specifically Diagnose Major Depressive Disorder (MDD)

In his latest “Zone in with Zon” blog post, dated May 26, 2015, and published by TriLink BioTechnologies of San Diego, Dr. Gerald Zon tackles the subject of depression and discusses the recent demonstration that a simple RT-PCR test can detect nine biomarkers (mRNA transcripts) that are specifically associated with, and diagnostic for, major depressive disorder (MDD). Furthermore, the test reliably predicts which MDD patients are likely to benefit from cognitive behavior therapy (CBT), and can also be used to measure biological changes resulting from CBT, thus potentially providing the first measurable, blood-based evidence of CBT’s success or failure. This new RT-PCR test constitutes the first-ever lab test that can specifically identify MDD. FDA approval of this unique new test could come as soon as early 2016, Dr. Zon states. And the need is great, Dr. Zon argues. Depression is a very common illness. The CDC estimates that one in ten U.S. adults suffer from depression, which reportedly costs close to $50B annually in lost productivity in the work place. Globally, more than 350 million people of all ages are afflicted with depression, according to recent statistics from the World Health Organization (WHO). By the year 2020, the WHO estimates that depression will be the second leading cause of “lost years of healthy life,” following heart disease. Normally, Dr. Zon says, “depression is diagnosed based on a patient’s self-reporting of symptoms and the evaluation of one or more structured psychiatric interviews with the patient by a psychiatrist, psychologist, or primary care physician.

May 26th

A Dyslexia Risk Gene Is Associated with Impaired Visual Motion Detection

A risk gene for dyslexia is associated with impairments in visual motion detection, according to a study published online on May 27, 2015 in The Journal of Neuroscience. Mutations in the gene DCDC2 have previously been associated with dyslexia, and this study found that dyslexics with an altered copy of the gene are unable to detect certain types of visual motion. The researchers used a series of visual tests to compare typical readers with two groups of dyslexics -- one group with and one group without a specific deletion in the DCDC2 gene. The subjects were presented with images of patterned black and white lines and asked to determine whether the image was moving horizontally or vertically. Dyslexics with the genetic deletion failed to detect the motion of the image, although they were able to determine the orientation of the lines. The group of dyslexics with a normal copy of the DCDC2 performed similarly to the normal readers, with only a minor impairment in motion detection. "This is the first paper I am aware of demonstrating a genetic marker that distinguishes between dyslexics with deficits in motion perception and those without," says Dr. Joseph LoTurco, a neuroscientist at the University of Connecticut who studies brain development and was not involved in the study. "It could be extremely valuable in future studies designed to discover optimal intervention strategies, and in early detection for children at risk for dyslexia." Readers should also be aware of an independent study published online on May 25, 2015 in Pediatrics that found essentially no association between dyslexia and vision problems and suggested that vision-based therapies are unlikely to be helpful in this condition. It was not clear from the article abstract whether or not visual motion detection was evaluated in the study published in Pediatrics.

ACMG Says "ClinGen" Knowledge Base Will Be Critical Resource for Interpretation of Genome-ScaleTesting to Improve Patient Care

Tremendous advances have been made in decoding the human genome in recent years but critical questions remain regarding what these variants mean and how they can be applied in clinical practice. In a comprehensive, open-access, special report published online on May 27, 2015 in The New England Journal of Medicine, and titled "ClinGen: The Clinical Genome Resource," a consortium including investigators from the American College of Medical Genetics and Genomics (ACMG) provide a detailed overview of ClinGen, an NIH-supported program to evaluate the clinical relevance of genetic variants for use in precision medicine and to increase the understanding of their role in human health and disease. ACMG Executive Director Michael S. Watson, Ph.D., FACMG, said, "With ClinGen and ClinVar now in place to manage the big data problem inherent in medical genomics, we are well positioned to enable extensive data sharing among laboratories and clinician. This is expected to dramatically improve our understanding of the clinical implications of genetic variation and its role in improving patient and population health." ClinGen's mission is to build a genomic knowledge base to improve patient care. Genetic clinicians and medical researchers hope to use information about genetic variants in a variety of ways including making better predictions about an individual’s risk of disease, to developing tailored treatments and to improve clinical decision-making.

May 26th

New Report on Microglia Cells & Chronic Pain

Chronic pain affects hundreds of millions of people worldwide and is a major cause of disability, causing more disability than cancer and heart disease. Canadian researchers, including Dr. Michael Salter at The Hospital for Sick Children (SickKids) in Toronto, are shedding new light on the molecular dynamics of chronic pain. They have uncovered a critical role in pain for a class of cells present in the brain and spinal cord, called microglia. They have found microglia-to-neuron-signaling to be crucial in the development of pain hypersensitivity after injury, but also for one of the paradoxical effects that morphine and other opioids sometimes produce, called hyperalgesia, which is an increase in pain sensitivity. The identification of these key players in the development of chronic pain helps identify important targets for the development of novel therapeutic avenues. Dr. Salter presented his team’s latest results at the 9th Annual Canadian Neuroscience Meeting, on May 26, 2015 in Vancouver, British Columbia. This meeting is being held from May 24 to May 27, 2015. "We're developing a new understanding of the control of microglia-neuron interactions that may be critical for individualizing pain therapies" said Dr. Salter. Pain is a complex experience. The International Academy for the Study of Pain (IASP) defines it as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage." While acute pain can be useful, as a signal that protects us from injury or even death, and inflammatory pain can protect us during healing, chronic neuropathic pain, which is a disease of the nervous system, is pain that persists after an injury is healed, serves no useful function, and is a major cause of disability. Work done in Dr.

Eleven Different Species of Panther Chameleon Newly Identified in Madagascar; Subtle Color Differences Associated with the Different Species

Madagascar is home to extraordinary biodiversity, but in the past few decades, the island's forests and associated biodiversity have been under greater attack than ever. Rapid deforestation is affecting the biotopes of hundreds of species, including the panther chameleon (photo, copyright Dr. Michel Milinkovitch), a species with spectacular intra-specific color variation. A new study by Dr. Michel Milinkovitch, Professor of Genetics, Evolution, and Biophysics at the University of Geneva (UNIGE), led in close collaboration with colleagues in Madagascar, reveals that this charismatic reptilian species, which is only found in Madagascar, is actually composed of eleven different species. The results of this new research appears were published online on May 24, 2015 in an open-access article in Molecular Ecology. The authors also discuss the urgent need to protect Madagascar's habitats. In collaboration with Professor Achille Raselimanana of the University of Antananarivo in Madagascar, researchers from the Department of Genetics and Evolution in the UNIGE Faculty of Sciences, led by Dr. Milinkovitch, sought to find the genetic keys behind the panther chameleon's incredible color palette. As noted, the team’s analyses, performed on site in Madagascar, revealed the presence of 11 rather than a single species. It took two expeditions led from East to West for the scientists to collect a drop of blood from each of 324 individual pather chameleons and document them through color photographs. The DNA (mitochondrial and nuclear) of each of the specimens was sequenced and analyzed in the laboratory according to the hypothesis that a chameleon's dominant color might be related to the geographic zone where it is found.

Scientists Reverse Aging in Human Cell Lines; Epigenetic Regulation, Not Mutations, Appears to Determine Age-Associated Defects in Mitochondria; Work Suggests Glycine Treatment May Reverse Age-Associated Mitochondrial Respiration Defects in Elderly

Can the process of aging be delayed or even reversed? Research led by specially appointed Professor Jun-Ichi Hayashi (photo) from the University of Tsukuba in Japan has shown that, in human cell lines at least, it can. They also found that the regulation of two genes involved with the production of glycine, the smallest and simplest amino acid, is partly responsible for some of the characteristics of aging. Professor Hayashi and his team made this exciting discovery while in the process of addressing some controversial issues surrounding a popular theory of aging. This theory, the mitochondrial theory of aging, proposes that age-associated mitochondrial defects are controlled by the accumulation of mutations in the mitochondrial DNA. Abnormal mitochondrial function is one of the hallmarks of aging in many species, including humans. This is mostly due to the fact that the mitochondrion is the so-called powerhouse of the cell as it produces energy in a process called cellular respiration. Damage to the mitochondrial DNA results in changes or mutations in the DNA sequence. Accumulation of these changes is associated with a reduced lifespan and early onset of aging-related characteristics such as weight and hair loss, curvature of the spine and osteoporosis. There is, however, a growing body of conflicting evidence that has raised doubts about the validity of this theory. The Tsukuba team in particular has performed some compelling research that has led them to propose that age-associated mitochondrial defects are not controlled by the accumulation of mutations in the mitochondrial DNA but by another form of genetic regulation.

May 25th

Vaccines Using Recombinant Newcastle Disease Virus and Influenza Virus Effective Against Two New Strains of Avian Influenza Virus (H5N1 and H7N9)

A recent study by Kansas State University researchers and colleagues details vaccine development for two new strains of avian influenza that can be transmitted from poultry to humans. The strains have led to the culling of millions of commercial chickens and turkeys, as well as to the deaths of hundreds of people. The new vaccine development method is expected to help researchers make vaccines for emerging strains of avian influenza more quickly. This could reduce the number and intensity of large-scale outbreaks at poultry farms as well as curb transmission to humans. It may also lead to new influenza vaccines for pigs, and novel vaccines for sheep and other livestock, said Dr. Jürgen Richt, Regents Distinguished Professor of Veterinary Medicine and Director of the U.S. Department of Homeland Security's Center of Excellence for Emerging and Zoonotic Animal Diseases. Dr. Richt and his colleagues focused on the avian influenza virus subtype H5N1, a new strain most active in Indonesia, Egypt, and other Southeast Asian and North African countries. H5N1 also has been documented in wild birds in the U.S., though in fewer numbers. "H5N1 is a zoonotic pathogen, which means that it is transmitted from chickens to humans," Dr. Richt said. "So far, it has infected more than 700 people worldwide and has killed about 60 percent of them. Unfortunately, it has a pretty high mortality rate." Researchers developed a vaccine for H5N1 by combining two viruses. A vaccine strain of the Newcastle disease virus, a virus that naturally affects poultry, was cloned and a small section of the H5N1 virus was transplanted into the Newcastle disease virus vaccine, creating a recombinant virus. Tests showed that the new recombinant virus effectively vaccinated chickens against both Newcastle disease virus and H5N1 influenza virus.

Certain Blind Individuals Use Echolocation As Replacement for Vision

Certain blind individuals have the ability to use echoes from tongue or finger clicks to recognize objects in the distance, and some use echolocation as a replacement for vision. Research done by Dr. Mel Goodale, from the University of Western Ontario, in Canada, and colleagues around the world, is showing that echolocation in blind individuals is a full form of sensory substitution, and that blind echolocation experts recruit regions of the brain normally associated with visual perception when making echo-based assessments of objects. Dr. Goodale is Director of the Brain and Mind Institute at the University of Western Ontario. He holds the Canada Research Chair in Visual Neuroscience. Dr. Mel Goodale is the 2015 Presidential Lecturer at the 9th Annual Canadian Neuroscience Meeting. Dr. Goodale's latest results were presented at the 9th Annual Canadian Neuroscience Meeting, on May 24, 2015 in Vancouver British Columbia. This meeting is being held May 24 to 27, 2015. "Our experiments show that echolocation is not just a tool to help visually-impaired individuals navigate their environment, but can act as an effective sensory replacement for vision, allowing them to recognize the shape, size, and material properties of objects," says Dr. Goodale. Just like multiple properties (size, expected weight, texture, composition) of an object assessed by visual cues are encoded in different brain regions, recent research carried out in the Goodale laboratory shows that the same is true of information obtained through the auditory cues provided by echolocation. Indeed, many of the same regions in the sighted brain that are used for the visual assessment of objects are recruited in the blind brain when objects are explored using echolocation.

Plant Receptors with Built-In Decoys Detect Pathogens and Raise Alarm

Receptors carrying built-in decoys are the latest discovery made in studying the evolutionary battle between plants and pathogens. The decoy domains within the receptor detect pathogens and raise the cell's alarm when there is an infection. Plants display component parts of their immune system on receptors to trick pathogens into binding with them, which then triggers defense mechanisms. The discovery comes from Professor Jonathan Jones' group at The Sainsbury Laboratory in the UK, and was published in the May 21, 2015 issue of Cell, together with a companion paper on a similar discovery from Dr. Laurent Deslandes’ group at the CNRS in Toulouse, France. The Jones article is titled “A Plant Immune Receptor Detects Pathogen Effectors that Target WRKY Transcription Factors.” The Deslands article is titled “A Receptor Pair with an Integrated Decoy Converts Pathogen Disabling of Transcription Factors to Immunity.” Pathogens target key parts of the plant's defense machinery in their attempts to suppress an immune response. Plants have evolved to display these targets on receptors that are primed to set off their alarm system. When the pathogen binds, the receptor starts the process of shutting down the cell to contain the pathogen and stop it from spreading. The research from Professor Jones' group shows one way in which plants perceive pathogens. Perception of pathogens is essential for immunity. Plants have very efficient defense mechanisms to stop a pathogen, if they can detect it soon enough. In turn, pathogens are constantly evolving to become stealthier so as to evade perception by the host. This arms race means both plant and pathogen are constantly under pressure to evolve new ways to outwit each other. Scientists now know these ways include the integration of decoy domains within receptors.