

Click to view It's clear that there's a specific set of genes responsible for brain development when you're in the womb, and that those genes affect your ability to learn later on. But now a group of researchers in the U.S. and Canada have identified those genes. And their discovery could represent the first step in tweaking brain development. It's possible that that knocking out some of those genes or adding extra copies of them to a developing baby could result in the tailor-made human minds of Brave New World: Some will be born to develop cutting-edge technologies, and others to be slow-witted and compliant.

Published this weekend in PLoS Genetics, the study is extraordinary not just because of its futuristic implications, but because of the cool new super-rapid system the researchers used to identify which genes are active during brain development. The technique is called RNA interference, or RNAi:

Dr. Katharine Sepp and her fellow researchers took fresh neuronal cells extracted from embryos of the fruit fly genus Drosophila and screened them using RNA interference techniques. The team tested all genes, one by one in a rapid manner, for their potential role in neuronal development. The team then validated the method in mice.

A combination of live-cell imaging and quantitative analysis allowed Sepp et al to characterize neurons' morphological phenotypes in response to RNAi-mediated gene knockdown. The researchers focused on 104 evolutionary conserved genes that, when downregulated by RNAi, have morphological defects. The team developed algorithms to help streamline the analysis of the thousands of images created in the process.

The analysis revealed unexpected, essential roles in neurite outgrowth for genes representing a wide range of functional categories including signalling molecules, enzymes, channels, receptors, and cytoskeletal proteins. Results also determined that genes known to be involved in protein and vesicle trafficking show similar RNAi phenotypes.

The researchers believe that this study provides an effective method for future studies of a large variety of genes, including those with important functions in the nervous system.

This research will open up new ways to tinker with brain development, but right now the genes have only been identified in flies and mice. Humans share a lot of genes with both creatures. Still, don't expect to order your supergenius baby next week. Or your army of slave drones.

Identification of Neural Outgrowth Genes Using Genome-Wide RNAi [PLoS Genetics]