New Research Sheds Light On What Makes The Human Brain Unique

Research from scientists astatine University of California San Diego School of Medicine person shed caller ray connected an age-old question: what makes nan quality encephalon unique?

The team's find comes from their investigation of human-accelerated regions (HARs) - sections of nan quality genome that person accumulated an unusually precocious level of mutations arsenic humans person evolved. There is simply a batch of technological liking successful HARs, arsenic they are hypothesized to play an basal domiciled successful conferring human-specific traits, and besides person links to neurodevelopmental disorders, specified arsenic autism.

One logic why scientists deliberation that HARs confer human-specific traits is because they person undergone accelerated changes successful their familial sequences since we divided from our closest surviving relative-the chimpanzee-approximately 5 cardinal years ago.

Now, UC San Diego researchers person identified 1 peculiar HAR-called HAR123-that appears to beryllium instrumental successful shaping nan quality brain.

The researchers found:

• HAR123 itself is not a gene, but is alternatively a type of molecular "volume control" known arsenic a transcriptional enhancer. Transcriptional enhancers power which genes are activated, really overmuch they are activated, and astatine what times they are activated during an organism's development.
• Through its domiciled arsenic a transcriptional enhancer, HAR123 promotes nan improvement of neural progenitor cells, nan cells that springiness emergence to nan 2 main types of encephalon cells - neurons and glial cells.
• HAR123 besides influences nan ratio of neurons and glial cells that shape from neural progenitor cells. 

Ultimately, HAR123 promotes a peculiarly precocious quality trait called cognitive flexibility, aliases nan expertise to unlearn and switch erstwhile knowledge.

In summation to providing caller insights into nan biology of nan quality brain, nan results besides connection a molecular mentation for immoderate of nan extremist changes that person occurred successful nan quality encephalon complete nan people of our evolution. This is supported, for example, by nan authors' uncovering that nan quality type of HAR123 exerts different molecular and cellular effects than nan chimpanzee type successful some stem cells and neuron precursor cells successful a petri dish.

Further investigation is needed to much afloat understand nan molecular action of HAR123 and whether nan quality type of HAR123 does so confer human-specific neural traits. This statement of investigation could lead america to a amended knowing of nan molecular mechanisms underlying galore neurodevelopmental disorders, specified arsenic autism.

The study, published online successful Science Advances, was led by Miles Wilkinson, Ph.D., distinguished professor, and Kun Tan, Ph.D., adjunct professor, some wrong nan Department of Obstetrics, Gynecology, & Reproductive Sciences astatine UC San Diego School of Medicine. Wilkinson is besides connection module of nan UC San Diego Institute for Genomic Medicine. The study was funded, successful part, by grants from nan National Institutes of Health and 10x Genomics.