In seeking the biological answer to the question of what it means to be human, the brain’s cerebral cortex is a good place to start. This densely folded, outer layer of grey matter, which is vastly larger in Homo sapiens than in other primates, plays an essential role in human consciousness, language, and reasoning.
Now, an NIH-funded team has pinpointed a key set of genes—found only in humans—that may help explain why our species possesses such a large cerebral cortex. Experimental evidence shows these genes prolong the development of stem cells that generate neurons in the cerebral cortex, which in turn enables the human brain to produce more mature cortical neurons and, thus, build a bigger cerebral cortex than our fellow primates.
That sounds like a great advantage for humans! But there’s a downside. Researchers found the same genomic changes that facilitated the expansion of the human cortex may also render our species more susceptible to certain rare neurodevelopmental disorders.
Posted In: News
Tags: autism, Autism Spectrum Disorder, brain, cerebral cortex, cortical neurons, CRISPR/Cas9, DNA sequencing, duplication, evolution, gene-editing technology, genes, genomics, human genome, Human Genome Project, humans, macrocephaly, microcephaly, microdeletion, neurodevelopmental disorders, neurons, neuroscience, Notch, organoids, primates, radial glial stem cells, schizophrenia, signaling genes, stem cells
Chances are you know someone with obsessive-compulsive disorder (OCD). It’s estimated that more than 2 million Americans struggle with this mental health condition, characterized by unwanted recurring thoughts and/or repetitive behaviors, such as excessive hand washing or constant counting of objects. While we know that OCD tends to run in families, it’s been frustratingly difficult to identify specific genes that influence OCD risk.
Now, an international research team, partly funded by NIH, has made progress thanks to an innovative genomic approach involving dogs, mice, and people. The strategy allowed them to uncover four genes involved in OCD that turn out to play a role in synapses, where nerve impulses are transmitted between neurons in the brain. While more research is needed to confirm the findings and better understand the molecular mechanisms of OCD, these findings offer important new leads that could point the way to more effective treatments.
Tags: ASD, autism, Autism Spectrum Disorder, brain, citizen science, compulsive behavior, CTTNBP2, Darwin's Dogs, DNA, DNA sequencing, Doberman Pinscher, dogs, gene variants, genomics, German Shepherd, HTR2A, Jack Russell terrier, mental health, mental illnesses, neurology, non-coding DNA, NRXN1, obsessive-compulsive disorder, OCD, pets, REEP3, regulatory elements, repetitive thoughts, serotonin, serotonin reuptake inhibitors, Shetland Sheepdog, SSRI, synapse
Research shows that the roots of autism spectrum disorder (ASD) generally start early—most likely in the womb. That’s one more reason, on top of a large number of epidemiological studies, why current claims about the role of vaccines in causing autism can’t be right. But how early is ASD detectable? It’s a critical question, since early intervention has been shown to help limit the effects of autism. The problem is there’s currently no reliable way to detect ASD until around 18–24 months, when the social deficits and repetitive behaviors associated with the condition begin to appear.
Several months ago, an NIH-funded team offered promising evidence that it may be possible to detect ASD in high-risk 1-year-olds by shifting attention from how kids act to how their brains have grown . Now, new evidence from that same team suggests that neurological signs of ASD might be detectable even earlier.
Tags: ASD, autism, Autism Spectrum Disorder, brain, brain connectivity, brain connectivity maps, brain development, brain scans, childhood disease, childhood vaccinations, computer learning, diagnosis, early detection, fMRI, Functional magnetic resonance imaging, imaging, infants, machine learning, neuroimaging, neurology, vaccines
Writers have The Elements of Style, chemists have the periodic table, and biomedical researchers could soon have a comprehensive reference on how to make neurons in a dish. Kristin Baldwin of the Scripps Research Institute, La Jolla, CA, has received a 2016 NIH Director’s Pioneer Award to begin drafting an online resource that will provide other researchers the information they need to reprogram mature human skin cells reproducibly into a variety of neurons that closely resemble those found in the brain and nervous system.
These lab-grown neurons could be used to improve our understanding of basic human biology and to develop better models for studying Alzheimer’s disease, autism, and a wide range of other neurological conditions. Such questions have been extremely difficult to explore in mice and other animal models because they have shorter lifespans and different brain structures than humans.
Tags: 2016 NIH Director’s Pioneer Award, addiction, aging, aging brain, Alzheimer’s disease, anxiety, autism, brain, brain cells, dopamine, fibroblasts, human neurons, iN cells, induced Pluripotent Stem cells, iPSCs, mental illness, neurobiology, neurology, neuronal subtypes, neurons, nicotinic receptors, serotonin, The Periodic Table, transcription factors, wellderly