MAP-seq: The New Way to Study the Brain
Mapping the neural connections between brain cells in an efficient manner is an issue for neurologists today. Most methods require the use of a microscope or fluorescent protein injection; these are sub-optimal approaches that are either incredibly laborious (the former) or simply inadequate for analyzing neural networks simultaneously (the latter). Unfortunately, these methods were all scientists, doctors and researchers had at their disposal to study the brain. Until recently.
Dr. Anthony Zador, neurologist and assistant professor at Stony Brook University, has devised a new technique for effectively examining neural networks to determine how different regions of the brain are connected to one another. This new approach, MAP-seq, works by “first creating a library of viruses that contain randomized RNA sequences…injected into the brain.” A single virus then invades a neuron and grants “the cell a unique RNA bar code.” What separates MAP-seq from other similar techniques is that this bar code can travel between connected neurons; since a multitude of viruses inject their RNA bar codes into several neurons simultaneously, a plethora of distinct (or even shared) pathways can be observed at the same time. A DNA sequencer can then be used to read these bar codes; researchers “create a connectivity matrix that displays how individual neurons connect to other regions of the brain” based on the accrued data.
The implications MAP-seq has on the field of neurology are astounding. By giving scientists a way to map neural networks on a grand scale in a faster period of time, Dr. Zador has revolutionized the way disorders and genetic mutations rooted in abnormal neural connectivity can be studied. If we visualize the brain as an amalgamation of distinct components comprised of millions of neurons, we can understand why this is the case. A certain region of the brain contains neurons that connect to various other regions’ brain cells; a MAP-seq analysis of these pathways might not only indicate ties of strong connections between cells, but can also imply where pairs of neurons have a strong/weak link by the principle of Strong Triadic Closure. If we generalize this example to each region of the brain, we get an incredibly intricate map that exposes how different regions of the brain relate to each other.
Dr. Zador has stated that “his lab is the only one bar-coding the brain, but…hopes others will start using MAP-seq to chart the brain’s circuitry.” MAP-seq is already showing great promise, and hopefully will serve as the basis for future advanced methods to study and decode the intrinsic pathways of the brain.
Article: https://www.technologyreview.com/s/602203/new-brain-mapping-technique-captures-every-connection-between-neurons/