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Extrapolation studies discover single gene that creates human brain

normal vs. microcephalic brain/Yale School of Medicine

In “Mutations in Single Gene May Have Shaped Human Cerebral Cortex” (ScienceDaily, Apr. 28, 2011), we encounter a surprising claim:

The size and shape of the human cerebral cortex, an evolutionary marvel responsible for everything from Shakespeare’s poetry to the atomic bomb, are largely influenced by mutations in a single gene, according to a team of researchers led by the Yale School of Medicine and three other universities.

The findings, reported April 28 in the American Journal of Human Genetics, are based on a genetic analysis of in one Turkish family and two Pakistani families with offspring born with the most severe form of microcephaly. The children have brains just 10 percent of normal size. They also lacked the normal cortical architecture that is a hallmark of the human brain. This combination of factors has not been seen in other genes associated with the development of the human brain, the authors note.

The researchers found that mutations in the same gene, centrosomal NDE1, which is involved in cell division, were responsible for the deformity.

From which they extrapolate,

“These findings demonstrate how single molecules have influenced the expansion of the human cerebral cortex in the last five million years,” Gunel said. “We are now a little closer to understanding just how this miracle happens.”

Bump. All they’ve really discovered is that NDE1 is a necessary component of healthy brain development. Along with hundreds of others whose malfunction could cause deficits, minor or severe. The rest is pure extrapolation.

With all this hype blowing around, if they ever do find anything really significant, how will we know?

news: can I ask you to correct your headline? Elizabeth Liddle
Well, read my posts for meaning, please, Mung! I try to choose my words precisely. Yes, genes can specify substantial changes in morphology. As it happens, I'm currently working on a paper in structural brain imaging genetics, on alleles that seem to have a substantial influence on cortical folding. That doesn't mean that that gene creates cortical folding, and certainly not a brain. The reason hox genes are interesting is that they are phylogenetically old, and kick in early during development. They do not specify the whole body, but do specify the cascade that specifies the whole body - and that cascade consists of lots of different genes. Elizabeth Liddle
Start here
And Sean Carroll explains, at a detailed genetic level, just how small changes to genes can specify radically different body plans.
Yes, I'd quite like to know where I argued that as well :) Elizabeth Liddle
Mung, Link or quote. WilliamRoache
And yet elsewhere Elizabeth argues that hox genes do just that. Mung
You are absolutely right, Joseph. Elizabeth Liddle
That mutations to a single gene can cause deformities does not mean that gene creates the very thing it can deform. Joseph
News - your own headline is not even a paraphrase of the headline of the article you cite. And I wouldn't go to ScienceDaily anyway as my authority on what scientists think they have found. But your own headline parodies the simplistic ScienceDaily one (which isn't bad, actually) to the point of outright misrepresentation, IMO. I'm not saying it's deliberate, I hasten to add, but I do think it's a bit irresponsible not to check the complete non-correspondence between: "Extrapolation studies discover single gene that creates human brain" and "Mutations in Single Gene May Have Shaped Human Cerebral Cortex" Note the difference between "discover...creates [human] brain" and "may ... shaped [human] cerebral cortex". The brain is not the cortex; the shape of the cortex is not the cortex; a gene that shapes the cortex does not create a brain; may have =/= did; To echo your final rhetorical question: With all this hype blowing around, if they ever do find anything really significant, how would the readers of UD news know? *scowls and mutters about quarter-baked science journalism* Having said all that - thanks for the link. It's an interesting finding :) Elizabeth Liddle
Wow! And I thought I had already witnessed everything about neo-darwinian stupidity... I must say that I am now a little closer to understanding how the amazing paradox of darwinian mentality happens. gpuccio
Mutations in a single gene produced the following? http://www.youtube.com/watch?v=hEnfZjqMSy0 How do these Darwinist clowns expect to be taken seriously by anyone with an IQ above room temperature? GilDodgen

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