Posts Tagged ‘stem cells’

The End of Human Evolution, or the Beginning?

March 25, 2008

Recently, researchers at Washington University school of Medicine in St Louis announced that they had corrected a genetic mutation in a fish embryo prior to birth. More importantly, they announced that the research could lead to the prevention of up to one fifth of birth defects in humans caused by genetic mutation.

While I will avoid the over discussed topic of when does an embryo become a human, it made me wonder whether we would be actively interfering in human evolution. One of the precepts of evolution is that mutation id often occurring as a form of trial and error in which we bring about new and improved (read more successful) forms of life. Now, I do think a portion of the creationist argument against human evolution is the notion that we might continue to evolve. Afterall, if we are already in God’s image, how can that be improved upon?

 But even with the massive success of homo sapiens on this planet, nothing seems to assure us that a sudden mutation may not offer some improved form of human (the variety of possible mutations is huge). Additionally, as we go on to explore and possibly colonize other planets, the mutative effects of lesser gravity and increased radiation will forcibly engender changes in the humans born under those conditions. If they are to survive, I suppose the ones with improved adaptability will be displaying some features or functions that will help them be more successful in their environment. Remember that Darwin claimed that evolutionary success was not about survival of the strongest or smartest, but of those most able to adapt. In fact, although it may be difficult to imagine, a dumber human that had other attributes that permitted for better survival might be an evolutionary improvement from Darwin’s point of view.

 What the Washington U announcement got me thinking was what if we use this wonderous medical break-through to put a halt to hap hazard mutational changes.

Despite the political will to try to stop people from experimenting with stem cells and human genetic manipulation, it is rather unrealistic to imagine that it will not occur (even though we may legally declare that a genetically modified human is not a human , much the same way certain European politicians are trying to do with GM corn).

 So, if humans begin to prevent mutations and actively change themselves, does that mean evolution (in the traditional format that we have come to know and argue about) is coming to an end or are we just about to begin.

 To add a little extra thought to this, remember that dogs as a species are only about 10,000 years old (obviously human developed from wolves) and that the vast majority of dog breeds are less than 500 years old. We are not strangers to altering the evolution of life forms.

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Make my brain more plastic fantastic please

March 11, 2008

In the 1967 film “The Graduate,” Mr. McGuire offers one word of advice to
Dustin Hoffman’s character, Benjamin Braddock: “Plastics”

Now-a-days, one can hardly tune into a PBS television channel without running into what is primaily an infomercial about exercising your brain in a brain gym.

The show, interestingly, explains the concept of brain plasticity, essentially the changes that occur in the organization of the brain as a result of experience.

We used to believe that once you achieved adulthood, large portions of your brain were set forever and that when portions were lost due to an accident, aging or abundant cheap vodka, these portions and their functions were irretrievably lost. Brain plasticity says, “uh-uh we have seen different functions move to different parts of the brain depending on environmental effects.”

The idea behind brain exercise is that you can keep your brain more plastic (able to change and adapt) by lifting mental dumbbells.

And now, a new article published in BMC Neuroscience seems to claim that injecting human umbilical cord  blood intravenously can actually increase neurogenesis in the brain.

This means an adult brain could begin acting like a growing brain once again. The first tests have been conducted on aging rats.  Rejuvenating an aging rats brain and making note of a change in behavior must have been a thrilling assignment (Wow! My rat has stopped playing dominoes and is hitting on the females again!).

A Google search of “umbilical cord blood” comes up with no less than 7 sponsored links touting the benefits of banking your newborns umbilical cord blood for later use. You can even get a kit for the collection of menstrual blood stem cells (did you ever imagine there was value there?). And special combo-packages can save you hundreds of dollars.

Who could have imagined that the fountain of youth and the birth canal could have been one and the same?