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Journal Journal: Biologists Demonstrate Inheritance of Traumatic "Memories" in Mice

Journal by wherrera

"One of the implications of the current Mendelian synthesis in molecular genetics is the idea that natural selection operates via selecting on random variations in the gene pool, which themselves are not influenced by the environmental experiences of the reproducing organisms. Changes of a given organism's body due to experience, such as conditioning, trauma, and memory, are usually assumed to only affect the gene pool of the next generation by influencing how many progeny are produced and ra

Submission + - Biologists Demonstrate Inheritance of Traumatic Memories in Mice

Submitted by wherrera
wherrera writes: One of the implications of the current Mendelian synthesis in molecular genetics is the idea that natural selection operates via selecting on random variations in the gene pool, which themselves are not influenced by the environmental experiences of the reproducing organisms. Changes of a given organism's body due to experience, such as conditioning, trauma, and memory, are usually assumed to only affect the gene pool of the next generation by influencing how many progeny are produced and raised by the prior generation. This is, however, not the whole story.

Epigenetics is the study of how gene expression changes during the growth and development of an organism. For example, the fertilized egg will divide and grow, not just into a clump of egg cells, but a fully differentiated organism containing many different kinds of specialized cells and tissues. Most of these calls contain the same genetic information as the original fertilized ovum, but the DNA has been subtly modified to make specialized groups of RNA and thus proteins.

The biology of epigenetics thus explains how the same DNA information produces different effects in different cells. Can such changes be inherited? Certainly in plants, they can be. It can be shown that sprouting root tissue from a tree often produces a differently shaped plant than sprouting a branch from the same tree. One way that this occurs is via methylation of the cytosine of a DNA region to make it into nonfunctional, mutation-promoting 5-methycytosine. When such changes in DNA--either in its cytosine or its associated histones--are passed to offspring, this has been called genetic imprinting.

In the journal Nature Neuroscience, Brian Dias and Kerry Ressler seem to have found a way that rodents use such genetic imprinting to create a survival advantage: via inheritance of fear of a certain smell. The researches seem to have found that conditioning an olfactory stimulus as adversive makes that stimulus' adversiveness inheritable in the offspring, and that this information is passed via a decreased methylation of the mouse's sperm DNA encoding those particular smell receptors as adversive to the mouse.

A future question is how a signal given to the nose can actually change the methylation of DNA in produced sperm. But we may have here an explanation for the rapid development of innate fear of a predator (including man) in the offspring of animals newly exposed to such.

Will Lamark score a partial comeback in biology? Time will tell.

Submission + - Alan Turing May Not Have Committed Suicied (bbc.co.uk)

Submitted by Frosty Piss
Frosty Piss writes: Alan Turing may not have committed suicide, as is widely believed. Turing expert Prof Jack Copeland has questioned the evidence that was presented at the 1954 inquest, believing that the evidence would not today be accepted as sufficient to establish a suicide verdict. In 1952, after he had reported a petty burglary, Turing found himself being investigated for "acts of gross indecency" after he revealed he had had a male lover in his house. Prof Copeland argues that on the contrary, Turing's career was at an intellectual high, and that he had borne his treatment "with good humour". Prof Copeland suggests that Turing's death was an accident.

Submission + - Google's Duplicitous Stance on Loopholes, Spirit of Law 2

Submitted by theodp
theodp writes: When it comes to tax loopholes, Google has certainly embraced the letter and not the spirit of the tax law. "Google plays by the rules set by politicians," quipped Google's UK head, defending the company's payment of a mere £6m in tax on sales of £2.6bn. "I view that you should pay the taxes that are legally required," added Google Chairman Eric Schmidt. "If the British system changes the tax laws then we will comply." So, one might ask whether Rap Genius was also playing by the letter of the rules, if not the spirit, when Google penalized Rap Genius for its link schemes. After all, don't they have the same fiduciary responsibility to investors that Google says motivates its tax strategy? Well, you could ask, but it wouldn't matter. In a case of what's-good-for-the-goose-is-not-good-for-the-gander, Google makes it clear that it won't countenance BS letter-of-the-law defenses from those who seek to exploit loopholes. From the Google Webmaster Guidelines, "These quality guidelines cover the most common forms of deceptive or manipulative behavior, but Google may respond negatively to other misleading practices not listed here. It's not safe to assume that just because a specific deceptive technique isn't included on this page, Google approves of it. Webmasters who spend their energies upholding the spirit of the basic principles will provide a much better user experience and subsequently enjoy better ranking than those who spend their time looking for loopholes they can exploit." So, in Lord Google's eyes, is exploiting loopholes good AND evil?

Submission + - Metamaterials Developed To Bend Sound Waves, Deflect Tsunamis (nydailynews.com)

Submitted by cold fjord
cold fjord writes: New York Daily News reports, "A new way of assembling things, called metamaterials, may in the not too distant future help to protect a building from earthquakes by bending seismic waves around it. Similarly, tsunami waves could be bent around towns, and sound waves bent around a room to make it soundproof. ... Metamaterials are simply materials that exhibit properties not found in nature, such as the way they absorb or reflect light. The key is in how they're made. By assembling the material — from photonic crystals to wire and foam — at a scale smaller than the length of the wave you're seeking to manipulate, the wave can, in theory, be bent to will. ... Ong and others say ... they could be used to redirect other kinds of waves, including mechanical waves such as sound and ocean waves. French researchers earlier this year, for example, diverted seismic waves around specially placed holes in the ground, reflecting the waves backward. Ong points to the possibility of using what has been learned in reconfiguring the geometry of materials to divert tsunamis from strategic buildings."

Comment OK, here is some math. (Score 5, Informative) 264

by wherrera (#45373679) Attached to: Tesla Fires and Firestorms: Let's Breathe and Review Some Car Fire Math

According to the US Bureau of Transportation,there are over 250 million cars on the road in the US. There are 150,000 fires in those vehicles a year __according to the OP__.

There are 20,000 Tesla cars, with 3 fires.

Relative risk = ( 3 / 20000 ) / ( 150000 / 250000000 ) = 0.00015 / 0.0006 = 0.25.

Get a Tesla, so as to avoid vehicle fires. Maybe? Depends on whether the reported stats are correct.

Comment Simulating completely or partially? (Score 3, Insightful) 393

by wherrera (#43735715) Attached to: Why We Should Build a Supercomputer Replica of the Human Brain

What exactly are "the functions of all 86 billion neurons"? I sense massive oversimplification here. Neurons have lots and lots of functions we have no idea how to simulate exactly, such as all the details of the thousands of networked internal metabolic mechanisms of any large mammalian cell, which most neural network simulations simply neglect.

Furthermore, we have plenty of evidence that the non-neuronal components of the brain (glia and oligodendroglia) massively influence brain functioning, and may be required for adequate cognition. Furthermore we have no way of knowing if a brain-in-a-vat will work the way a brain in the body, with all its connections, works. The above issues are just a start to the limitations of the scheme.

Comment Have you ever hiked around bison? Thought not. (Score 3, Interesting) 154

by wherrera (#43210381) Attached to: "Lazarus Project" Clones Extinct Frog

Herding bison? Bison are not endangered in at least past of the American West. Bison are not afraid of people or mountain cyclists, and are quite willing to trample and gore them if annoyed, and are annoyed fairly easily. They can run 40 mph for over a mile, can jump 5 vertical feet, and can walk right through and over most ordinary fences.

I very much doubt the older DNA has more placid traits.

Comment Re:Can't use - don't have optic rectum (Score 1) 25

by wherrera (#42769801) Attached to: Amazing Video of a Brain Perceiving the External World

Kidding right? That's Tectum, and in humans it is a structure in the midbrain (the human midbrain, part of the brainstem, is shaped a lot like the zebrafish organ in the video, by the way) that processes vision in a mostly pre-conscious way. So,in the zebrafish, we probably have to say that the tectum signaling in that video may not be the fish thinking, in the same way we do, at least. Google for blindsight.
Ubuntu

Submission + - Ubuntu 13.04 Will Allow Instant Purchasing, Right From The Dash (muktware.com) 1

Submitted by sfcrazy
sfcrazy writes: Ubuntu is becoming a shopping center. Instead of addressing the queries rasied by Stallman and EFF, Canonical is now pushing for making Ubuntu a shopping cart. " With Ubuntu 13.04 Canonical is going one step forward, and soon you will be able to purchase software and music right from the Dash without opening the software center or web browser. This is intended to make the whole experience even more interactive and useful for the end user."

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