Sunday, October 29, 2006

Genetic Inheritance By Paramutation

This came as a bit of a surprise to me. I was taught early on that we each inherited two sets of genes, one from our mother and one from our father in the form of DNA. These inherited genes were then responsible for all of our genetically governed traits. This article in the Economist (subscription required) suggests that

genetic information comes from places other than inherited DNA.

Based on studies of a gene called Kit French researches believe they have found that in some cases RNA can be passed from parent to child... but in this case RNA that has no relation to the DNA passed from that parent. In this manner, offspring may end up with RNA, and thereby DNA from a parent or grandparent, but lack the DNA that would have been expected to code for that RNA. The article states:
When this RNA was extracted and injected into mice embryos, a white-tailed mutant was created—even though no genes for the white tail were present. This work shows that the inheritance is mediated by RNA but the precise mechanism is unclear. The inherited RNA could be interfering with messages sent by the inherited DNA, or it could be directly modifying inherited DNA.

The phenomenon observed has been coined paramutation and is believe to be able to persist across generations, and has been grouped as an 'epigenetic' effect - defined in the article as
hereditary changes in gene function put down to chemical changes rather than the sequence of DNA.

From The Economist

Saturday, October 28, 2006

Tailor Made For Further Research

I'm sure some researches would love to get a hold of these kids and study them as they grow. Their mother is English-Nigerian and their father is white (thanks, that's nice and specific) but one twin has dark hair, brown eyes and brown skin while the other has blonde hair, blue eyes and pale skin.

Get ready for the stares kids.

Not Genetics-Related Per Se...

But (tongue in cheek) I'm about ready to go get tested for my predisposition to diabetes so that I can give these little treats a shot.

Hospitals across the US had better brace themselves for the influx of even bigger, beefier American kids if these take off.

...a batter mix made with Coca-Cola syrup, a drizzle of strawberry syrup, and some strawberries.

Balls of the batter are then deep-fried, ending up like ping-pong ball sized doughnuts which are then served in a cup, topped with Coca-Cola syrup, whipped cream, cinnamon sugar and a cherry on the top.

Wednesday, October 25, 2006

No More Cancer Deaths In 20 Years?

So says an Aussie expert. John Shine proposes that since we're able to target particular genes using 'smart drugs' we should be able to extend this benefit in the fight against cancer.

Shine is clear that he doesn't expect that people won't get cancer, but rather that they won't die from it. This is an interesting theory, and I hope he's right, but to be honest I'm still waiting for my jetpack ;)

Be Careful What You Hear

Or more specifically... be careful what you choose to believe. The press is getting broader and broader in terms of the topics that they choose to cover on a regular basis. Unfortunately they sometimes seem to be getting more and more liberal in their interpretation of these topics and the takeaways for those of us reading.

Genetics & Health briefly discusses the topic and suggests that while it remains a good idea to communicate risk to people outside of the medical genetics community, that communication should come with added education so that those individuals understand how to use it.

Is genetic testing worthwhile based on report X or would it provide very little likely benefit to you as an individual relative to the risk given your personal circumstances? The average person reading a paper or magazine is highly likely to draw the correct conclusion particularly when all-too-often the message is veiled in a sensationalist wrapping.

Lifestyle May Be More Important Than Genetics In Type 2 Diabetes Risk

On the heels of the 'genetics is a heavier influence than socio-economic factors in breast cancer' post comes this article suggesting that for Type 2 diabetes risk, a healthy lifestyle may hold genetic influences at bay - or at least trump them.

From the post

Genetics affects diabetes risk...but lifestyle is still the most important factor at play. That's the conclusion of a new study, which showed that a certain gene variant gives people a substantially increased risk for developing Type 2 - an eighty percent higher risk, in fact.

Sounds pretty nasty. However the article goes on to suggest that despite the above, a healthy lifestyle can successfully offset that genetic risk - lifestyle trumps genetics. In your eye mother nature!

Some Cancers Target More Aggressively By Race?

Here's an interesting blog post with links to the main article suggesting that certain black women may suffer from a more aggressive form of breast cancer than white women. This in turn would help to explain the differential survival rates between the two groups.

While its likely that socio-economic factors continue to play a role, this particular study appears to suggest that the larger factor may be a genetic one. The poster that I'm linking to here offers another interesting angle. S/he suggests that in addition to socio-economic and genetic factors one should consider looking at the nature of treatment for these cancers and how it is tailored to a white population.

While interesting to consider this on its own I'm not certain that it's not not just a variant of the two prior explanations. After all, if the treatments administered in identical circumstances don't target blacks as well as whites it's likely due to a) genetics or to some extent b) cultural or socio-economic factors.

Gotta love blanket categories :)

Monday, October 23, 2006

Melanoma, We Can Hear You...

The bloggers over at are writing about a team of scientists over at the University of Missouri-Columbia who can apparently detect cancer cells in an individuals blood by listening for them.

Apparently they're able to make the individual's cells vibrate and then recognize the unique pattern emitted by the cancer cells if present.

While melanoma is the only form of cancer detectable in this manner today, the test is said to be fast (done in 30 minutes) and minimally invasive... this could be an incredible win in the struggle against cancer.

Human Species May Split In Two

A creepy article on the BBC News website suggests that in the relatively near future Humanity (100,000 years' time) may split in two.

The article describes the two tracks as a genetic upper class and a 'dim-witted' underclass as a result of individuals becoming choosier about who they partnered with. The upper class is characterized in the article as being tall, slim, healthy, attractive and intelligent while the other branch is proposed to be dim-witted, ugly, squat and goblin-like.

Additionally, the authors propose that by this time race will have been effectively erased with all humans sharing a common skin tone, tall stature and long life span.

I'd love to read the original paper that spawned this article. It sounds more like a prime time science fiction program than serious science given the heavy bent used to describe the proposed changes. Check you in 100,000 years to see how accurate the prediction is!

Friday, October 20, 2006

Charles Darwin's Works Available Online

BBC News reports that the complete works of Charles Darwin are now published and available online - and searchable. Apparently there is no charge to use the website or its contents which are available in a number of versions and languages.

While the collection isnt' complete this is certainly a good start... particularly the downloadable audio files that are sure to make a science geek's commute that much more bearable.

Colorectal Cancer Slowed By Grape Seed Extract?

Medical News Today reports that a recent study documented:

a 44 percent reduction of advanced colorectal tumors in the animals, and also revealed, for the first time, the molecular mechanism by which grape seed extract works to inhibit cancer growth
Apparently the grape seed extract increases the presence of Cip1/p21 protein in tumours which stops the cell cycle, killing the cancer.

So here's the next problem. I'm pretty sure I saw grape seed extract in the supplements aisle at Safeway last week, but the article states that:
With these results, we are not suggesting that people run out and buy and use grape seed extract. That could be dangerous since so little is known about doses and side effects
I'll have mine by noon tomorrow.

Disease Prediction Made Fun

Sure, some people are predisposed genetically to certain conditions but we can often influence the degree to which they exhibit themselves by controlling our behavior and environment.

Harvard Center for Cancer Prevention offers this fun little test that will allow you to approximate your risk for particular diseases common in the US. While its only a guide, it will provide helpful hints at the end to assist you in altering your behavior to reduce the likelihood that you will get any of the conditions.

Give it a shot

Best Company Name Ever. Genetic Saving & Clone

What can I say... their pet cloning service may not have succeeded, but I'm thinking they can spin themselves into a branding firm.

According to Wired Genetic Saving & Clone will be closing its doors very shortly. Who would have thought that there wasn't a market for a $50,000 cloned cat - $32,000 after a last ditch price chop... a cat that would like bear little or no resemblance personality-wise to its loved predecessor.

As catchy as the firm's name may be I can only recall hearing about it recently. This despite the fact that it's been in operation for 6 years. 6 years and 2 cloned cats sold. That's a lot of starting at your cube-mate and playing solitaire waiting for a cat to gestate.

First mover advantage?
File this one under technology ahead of its time (if it has a time at all).

Depression & Early Life Stress

Genes and environment. One we can control, one we cannot.
Now it appears we may have less control over the environment factor than most of us assume. According to an article printed by Reuters yesterday early family life may have the ability to counter a 'depression gene.'

What's the depression gene? Per the article people who carry a short version of the serotonin transporter gene (5-HTTLPR) appear more susceptible to depression than those lacking the variant.

Interestingly, researchers claim that those people with the short version of the gene who grow up in lower stress environments were less likely to exhibit signs of depression.

In your eye nature. Score one for nurture. If only it were easier to control your environment as a child...

I'll leave it to you to look deeper into the study's methodology.