Brain growth and maturation doesn’t progress in a linear, stepwise fashion. Instead, it’s a dynamic, choreographed sequence that shifts in response to genetics and external stimuli like sight and sound. This is the first high-resolution growth chart to explain changes of key brain cell types in the developing mouse brain, led by a team at Penn State College of Medicine and the Allen Institute for Brain Science.

Using advanced imaging techniques, the researchers constructed a series of 3D atlases that are like time-lapsed maps of the brain during its first two weeks after birth, offering an unparalleled look at a critical period of brain development. It’s a powerful tool to understand healthy brain development and neurodevelopmental disorders, the researchers explained.

The study, published in Nature Communications, also detailed how regions of the brain change in volume and explained the shift in density of key cell types within them.

Motor neuron diseases, such as amyotrophic lateral sclerosis (ALS) and hereditary spastic paraplegia (HSP), share physical similarities but have been largely viewed as genetically distinct. However, an analysis led by investigators from St. Jude Children’s Research Hospital and the University of Miami Miller School of Medicine discovered that there are previously unknown ultrarare gene variants (genetic changes found in extremely few individuals) linked to the diseases, and significant overlap of contributing genes between the diseases among patients without family histories of a motor neuron disease.

This new appreciation of the shared genetic origins of different motor neuron diseases is critical to deciphering the origins of these disorders and ultimately developing meaningful therapeutics. The findings are published in Translational Neurodegeneration.

While both ALS and HSP cause progressive motor dysfunction, the two disorders also have distinct characteristics. Weakness in ALS may begin in the arms, legs, head or neck. HSP, by contrast, begins in the legs. The causative, or “canonical” genes for these diseases are also largely distinct.

Scientists have identified hundreds of genes that may increase the risk of developing Alzheimer’s disease but the roles these genes play in the brain are poorly understood. This lack of understanding poses a barrier to developing new therapies, but in a study published in the American Journal of Human Genetics, researchers at Baylor College of Medicine and the Jan and Dan Duncan Neurological Research Institute (Duncan NRI) at Texas Children’s Hospital offer new insights into how Alzheimer’s disease risk genes affect the brain.

“We studied fruit fly versions of 100 human Alzheimer’s disease risk genes,” said first author Dr. Jennifer Deger, a neuroscience graduate in Baylor’s Medical Scientist Training Program (M.D./Ph. D.), mentored by Drs. Joshua Shulman and Hugo Bellen.

“We developed fruit flies with mutations that ‘turned off’ each gene and determined how this affected the fly’s brain structure, function and stress resilience as the flies aged.”

An international research team, led by Shinghua Ding at the University of Missouri, has identified a previously unknown genetic disease that affects movement and muscle control.

The disease—called Mutation in NAMPT Axonopathy (MINA) syndrome—causes damage to motor neurons, the nerve cells that send signals from the brain and spinal cord to muscles. It’s the result of a rare genetic mutation in a critical protein known as NAMPT, which helps the body’s cells make and use energy. When this protein doesn’t work as it should, cells can’t produce enough energy to stay healthy.

Over time, this lack of energy causes the cells to weaken and die, and leads to symptoms such as muscle weakness, loss of coordination and foot deformities—which can worsen over time. In severe cases, patients may eventually need a wheelchair.