One of the great mysteries in biology is how we humans ended up with such large, complex brains. In search of clues, researchers have spent years studying the protein-coding genes activated during neurodevelopment. But some answers may also be hiding in non-coding regions of the human genome, where sequences called regulatory elements increase or decrease the activity of genes. A fascinating example involves a type of regulatory element called a human accelerated region (HAR). Although “human” is part of this element’s name, it turns out that the genomes of all vertebrates—not just humans—co ..read more

Credit: SciePro/Shutterstock; BRAIN Initiative Cell Census Network, Nature, 2021 The primary motor cortex is the part of the brain that enables most of our skilled movements, whether it’s walking, texting on our phones, strumming a guitar, or even spiking a volleyball. The region remains a major research focus, and that’s why NIH’s Brain Research Through Advancing Innovative Neurotechnologies® (BRAIN) Initiative – Cell Census Network (BICCN) has just unveiled two groundbreaking resources: a complete census of cell types present in the mammalian primary motor cortex, along with the first detail ..read more

Serotonin is best known for its role as a chemical messenger in the brain, helping to regulate mood, appetite, sleep, and many other functions. It exerts these influences by binding to its receptor on the surface of neural cells. But startling new work suggests the impact of serotonin does not end there: the molecule also can enter a cell’s nucleus and directly switch on genes. While much more study is needed, this is a potentially groundbreaking discovery. Not only could it have implications for managing depression and other mood disorders, it may also open new avenues for treating substance ..read more

Caption: Single-cell analysis helps to reveal subtle, but important, differences among human cells, including many types of brain cells. Credit: Shutterstock, modified by Ryan M. Mulqueen Imagine how long it would take to analyze the 37 trillion or so cells that make up the human body if you had to do it by hand, one by one! Still, single-cell analysis is crucial to gaining a comprehensive understanding of our biology. The cell is the unit of life for all organisms, and all cells are certainly not the same. Think about it: even though each cell contains the same DNA, some make up your skin w ..read more

Bradley Bernstein Inside our cells, strands of DNA wrap around spool-like histone proteins to form a DNA-histone complex called chromatin. Bradley Bernstein, a pathologist at Massachusetts General Hospital, Harvard University, and Broad Institute, has always been fascinated by this process. What interests him is the fact that an approximately 6-foot-long strand of DNA can be folded and packed into orderly chromatin structures inside a cell nucleus that’s just 0.0002 inch wide. Bernstein’s fascination with DNA packaging led to the recent major discovery that, when chromatin misfolds in brain ..read more

Keith Maggert To learn more about how DNA and inheritance works, Keith Maggert has spent much of his nearly 30 years as a researcher studying what takes place not just within the DNA genome but also the subtle modifications of it. That’s where a stable of enzymes add chemical marks to DNA, turning individual genes on or off without changing their underlying sequence. What’s really intrigued Maggert is these “epigenetic” modifications are maintained through cell division and can even get passed down from parent to child over many generations. Like many researchers, he wants to know how it hap ..read more

Caption: Oncologists review a close-up image of a brain tumor (green dot). Credit: National Cancer Institute Scientists have spent much time and energy mapping the many DNA misspellings that can transform healthy cells into cancerous ones. But recently it has become increasingly clear that changes to the DNA sequence itself are not the only culprits. Cancer can also be driven by epigenetic changes to DNA—modifications to chemical marks on the genome don’t alter the sequence of the DNA molecule, but act to influence gene activity. A prime example of this can been seen in glioblastoma, a rare ..read more

Caption: Genetically identical mice. The Agouti gene is active in the yellow mouse and inactive in the brown mouse. Credit: Dana Dolinoy, University of Michigan, Ann Arbor, and Randy Jirtle, Duke University, Durham, NC Step inside the lab of Dana Dolinoy at the University of Michigan, Ann Arbor, and you’re sure to hear conversations that include the rather strange word “agouti” (uh-goo-tee). In this context, it’s a name given to a strain of laboratory mice that arose decades ago from a random mutation in the Agouti gene, which is normally expressed only transiently in hair follicles. Th ..read more

Credit: Daniel Berehulak/Getty Images Despite years of public health campaigns warning of the dangers of smoking when pregnant, many women are unaware of the risk or find themselves unable to quit. As a result, far too many babies are still being exposed in the womb to toxins that enter their mothers’ bloodstreams when they inhale cigarette smoke. Among the many infant and child health problems that have been linked to maternal smoking are premature birth, low birth weight, asthma, reduced lung function, sudden infant death syndrome (SIDS), and cleft lip and/or palate. Now, a large internati ..read more

Caption: Remembering a few of the many children who’ve died of DIPG; Left, Lyla Nsouli and parents; upper right, Andrew Smith and mom; lower right, Alexis Agin and parents. Credits: Nsouli, Smith, and Agin families Every year in the United States, several hundred children and their families receive a devastating diagnosis: diffuse intrinsic pontine glioma (DIPG). Sadly, this inoperable tumor of the brain stem, little known by the public, is almost always fatal, and efforts to develop life-saving treatments have been hampered by a lack of molecular data to identify agents that might specifica ..read more