[Home] [Headlines] [Latest Articles] [Latest Comments] [Post] [Sign-in] [Mail] [Setup] [Help]
Status: Not Logged In; Sign In
|
Science/Tech See other Science/Tech Articles Title: Sociogenomics 1 July 07, 2009 Sociogenomics 1 I was one of a number of scholars lucky enough to be invited to the Illinois Politics and Biology Summer Institute, sponsored by the National Science Foundation. The Directors include Ira Carmen, a political scientist who writes extensively on genetics and politics, and Gene Robinson, a biologist who spends his time working on links between the genes and social behaviors of honey bees. The Institute is meeting at the Institute for Genomic Biology on the campus of the University of Illinois, Urbana-Champaign. The pace is pretty brutal for this kind of thing: eight solid hours a day of presentation and discussion. Most of the NSF fellows are youngsters by my standard: working on their Ph.D.s, or just finished. I am learning to settle in as the designated old fart. Today we covered the history of the American Political Science Association, founded in 1903 by, well, a bunch of Darwinists. But the APSA quickly ran away from biology following the historicist trend of the times. According to this latter perspective, human behavior and institutions were to be viewed as "socially constructed", that is, as if human beings constructed their institutions entirely apart from the natural world and its influences. There were some good reasons for this. In 1903 there just wasn't enough known about biology, genetics, or evolution to usefully guide the social sciences. When such knowledge did begin to become available, there was enormous resistance on the part of most political scientists. For one thing, they didn't want to have to learn any real science. For another, there was fear that biological explanations would limit social progress and support regressive political ideas. The coining of the phrase "Sociogenomics" (even the word genomics is rather new), indicates that the pendulum is finally swinging back toward nature as the foundation of a real political science. The second topic we focused on today, and the one that was deeply fascinating to me, is the shift in the view of genes and how they operate. Many of those who fear genetic explanations of human behavior have the idea that genes are fixed influences, so that if a gene codes for some kind of behavior, then a person or organism that has one version will act one way and a person or organism that has another version will act another way. This view is sometimes called genetic determinism. But it is not how genes work. Genes are composed of DNA and code directly for MRNA (which is now pronounced emarenay, I have learned). MRNA (messenger RNA) is used by cells to produce the proteins that in turn influence the structure and behavior and pretty much everything else that characterizes a living being. Now here is the really cool thing: while DNA is fixed (except when changed by mutation), the expression of the genes in different Messenger RNA messages is flexible. The way the Chromatin wraps around itself determines how the genes will be expressed in the fully realized organism. That in turn can be influenced by the environment. For example: adult honey bees ordinarily begin their careers as nurses, working to tend the larvae. After a few weeks the nurse graduates to the forager/soldier. It begins its self-guided education by taking a few test flights from the hive, orienting itself with respect to the sun and the location of its home. Once it begins foraging in earnest, it will know how to return to the hive and indicate the location of flowers by doing a very expressive dance. But sometimes the hive will lose many or most of its forgers when the environment turns against them. The forager secret a pheromone that alerts the nurse/workers to their presence and gives the latter a sense of how many foragers are coming in and out. When the pheromone concentration in the hive drops below a certain level, the expression of the foraging genes in the nurses changes and they become "precocious foragers" switching to the new role in the first week of their adulthood. Same genes. Different time table. Likewise, when mother mouse licks her young, this maternal care alters genes that give the young a lifelong resistance to stress, and helps trigger maternal instincts in the females. Again, the same genes are expressed in different brain structures and behavior. That is so cool. Genetic influence is not genetic determinism. Now, if I get this right, the genes that are under review in these examples exist as orthologs in human beings. An orthologs is a gene that exists in similar form in two species and that was inherited from a common ancestor. Some genes have been conserved with very little change over long stretches of evolutionary history. One of the themes of this institute is that we are beginning to correlate genes with behavior patterns in human beings. More on that tomorrow, I think. Of course, what we don't know and won't know for a while dwarfs what we do know. It may be possible to correlate this gene here with that behavior over there, but we know very little about the chain of causation that connects the one to the other. What we are learning is that genes do not cause behavior, let alone passions and experience. Rather, gene expression exists in a dynamic relationship with human structure, experience, and behavior, as is the case with other creatures. I think this is the greatest show on earth.
Post Comment Private Reply Ignore Thread Top • Page Up • Full Thread • Page Down • Bottom/Latest
#1. To: Prefrontal Vortex (#0)
|
||
|
[Home]
[Headlines]
[Latest Articles]
[Latest Comments]
[Post]
[Sign-in]
[Mail]
[Setup]
[Help]
|
||