Mice Created With Human Brain Cells 339
pin_gween writes "Scientists have added 100,000 human brain cells to mice in an effort to create realistic models of disorders like Parkinson's Disease. Although mice are 97.5 percent genetically identical to humans and it sounds like a large number, 100,000 only represents 0.1% of the number of cells in mice brains. FTA: 'It's true that there is a huge amount of similarity, but the differences are huge,' Snyder said. 'You will never ever have a little human trapped inside a mouse or monkey's body. [...] Researchers are nevertheless beginning to bump up against what bioethicists call the "yuck factor." 'The worry is if you humanize them too much you cross certain boundaries,' said David Magnus, director of the Stanford Medical Center for Biomedical Ethics. 'But I don't think this research comes even close to that.'"
Re:NARF! (Score:2, Informative)
I came up with this [tvshowsondvd.com]
We've got great news for you, then! Industry sources, speaking on condition of anonymity, have let us know that Warner Home Video has both of these animated series on their radar screen for a possible mid-2006 DVD release! Look for a multi-disc set for each show, with around two dozen episodes per box.
Re:brain simulation? (Score:2, Informative)
http://neuron.duke.edu/cells/ [duke.edu]
and modelled in something like:
http://www.neuron.yale.edu/neuron/ [yale.edu]
Even using vastly simplified neurons, like integrate & fire types, for example: http://www.nsi.edu/users/izhikevich/publications/
you still have many vastly different types of spiking behaviors.
You then still have to deal with the fact that neurons 'generally' connect to about ~10k others, (actual range something like 10-100k). And that's before you get to details like what neurons are where, with what densities, that long range connections in mammalian brains are generally not very well understood, etc. etc. etc.
The brain is a lot more complicated than you think. We're still many many years away from modeling a mouse brain, at a purely neuronal level. I mean, there still isn't a definitive model of the Aplysia, neuron count ~10k...
Re:Keeping a tally... (Score:4, Informative)
This has been another useless fact.
Check these out (Score:2, Informative)
Re:97.5% genetically identical (Score:2, Informative)
Even if you restrict yourself to the genes shared between mouse and human, the DNA sequences are not 97.5% identical. I don't remember the number off the top of my head, but it's somewhere closer to 90%.
Note that this 97.5% number is not in the scientific article -- I double checked on the website. It looks like a number that the newspaper guy pulled out of a hat, probably from some other book or study he'd read.
My guess is that 97.5% refers to some other, much more specialized calculation, e.g. the percent identity at the protein level of genes that have clear counterparts in mouse or human, or perhaps to the fraction of known genes in human that have a counterpart in mouse.
In any case, the newspaper writer screwed up. As it's written, the 97.5% identity statement is very misleading.