mapping efforts hit milestones
As the Brain Initiative announced by President Obama a year ago continues to set priorities and gear up for what researchers hope will be a decadelong program to understand how the brain works, two projects independent of that effort reached milestones in their mapping work.
Both projects, one public and one private, are examples of the widespread effort in neuroscience to create databases and maps of brain structure and function that can serve as a foundation for research. While the Obama initiative is concentrating on the development of new tools, that research will build on and use the data being acquired in projects like these.
One group of 80 researchers, working as part of a consortium funded by the National Institute of Mental Health, reported that it had mapped the genetic activity of the human fetal brain. Among other initial findings, the map, the first installment of an atlas of the developing human brain called BrainSpan, confirmed the significance of areas in the development of autism.
A group of 33 researchers, all but one at the Allen Institute for Brain Science, announced an atlas of the mouse brain showing the connections among 295 different regions.
Ed Lein, senior author on the fetal brain paper, said the research required making sections only 20 microns thick, up to 3,500 for each of four fetal brains. Researchers measured the activity of 20,000 genes in 300 brain structures.
One finding, Lein said, was that "95 percent of the genome was used," meaning almost all of the genes were active during brain development, significantly more than in adult brains. The team also found many differences from the mouse brain, underscoring the findings that, despite the many similarities in all mammalian brains, only so much can be extrapolated to humans.
JAMES GORMAN
