Researchers make a massive map of changes that our brain undergoes as an infant

Researchers from the St Jude’s Childrens’ Hospital have compiled a huge database with the many genetic changes that brain cells undergo as an embryo, and in the months immediately following birth. The findings from the study were published on 14 September in the journal Current Biology. The researchers isolated thousands of brain cells from a mouse model for the study. By isolating RNA from individual brain cells in embryonic and newborn mice, the researchers constructed a map of what genes were being switched on and off in these early developmental stages. While studying DNA can accurately describe what genes are present in the cell, looking at RNA molecules reveals which of genes are expressed, and when. Using a technique called single cell RNA-sequencing, researchers recorded the levels of different RNA molecules that were present in the cell. This information was used to create a high-resolution map of changes that cells in the cerebellum undergo in the prenatal and initial years of growth. [caption id=“attachment_5191441” align=“alignnone” width=“1280”] Representational image. Flickr[/caption] Their focus on cells of the cerebellum is a strategic one. While the cerebellum occupies just about 10% of the brain’s volume, it houses nearly half of all the nerve cells in the central nervous system (brain and spinal cord), the press release said. Of particular interest to them was how the circuits of neurons in this region grow and interconnect after birth. A sound understanding of how these processes happen, and the genes involved would open up areas of research into the genetic origins of many brain disorders during early development in humans. It could also enable studies looking at underlying causes for deadly childhood cancers like medulloblastoma (a brain tumour that begins in the embryonic stages), astrocytoma (in which ‘glial cells’ found in the brain and spinal cord become cancerous), and ependymoma (a paediatric forms of cancer that turns ‘ependymal cells’ that line the skull cancerous). “Since most brain tumors in young children occur in the cerebellar region, this will help us identify the cells of origin for different brain tumors and brain tumor subtypes,” Charles Gawad, a co-author of the study and researcher at the hospital, said to university press. The product of their research is freely available for other researchers to access in an online database called Cell Seek.