Genetic Future Weblog

Once again, studies of mitochondrial DNA have revealed something interesting about the ancestral origins of species:

Aug. 3, 2004 — Dingoes, Australia’s wild dogs, are descended from Asian domesticated dogs, not wolves, according to international research.
[Discovery Channel News, reporting on this PNAS abstract]

I love stuff like this. It reminds us that we humans (and our domesticated pets, for that matter) are not the pinnacle of evolution. More bad-ass stuff is yet to come. Take a look at this dingo, for example. Do you think Lassie would have a chance in an all-out claws and fangs battle with this puppy?

Kind of makes you wonder what house cats are going to evolve into…

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The NAS recently published a report (available as a book, or as a free download from here) which says that genetically modified food is no way substantially different from non-GM food. It says that GM foods, just like regular foods, carry risks. The report admits that GM technology can cause these risks to pop up in unlikely places (e.g. GM insect-resistant celery that gives farm workers severe skin rashes) but stops short of saying that GM food is in any way less “safe” than non-GM food.

More specifically, the NAS report says that the substances that compose GM food can’t be meaningfully distinguished from the substances in ordinary food. As such, the FDA is basically discouraged from treating GM food in a different way than regular food when it comes to safety.

Generally speaking, this report doesn’t alarm me in any way. It puts forward the point of view that most reasonable science-minded folks hold, that GM food doesn’t contain weird never-before-seen toxins, and that anyone who thinks that GM food is going to kill us is being a little foolish.

Unfortunately, it doesn’t do much to promote GM food labeling. There are a lot of reasons we should require GM food to be labeled as such. For one thing, there are a lot of folks who don’t want to help finance companies that are participating in the GM food industry. While GM food is probably safe for us, it’s too early to tell whether or not it’s going to mess up our ecosystem. Many consumers would like to vote with their dollars, and spend their money on traditional foods instead of jumping head-first into GM technology.

Also, while GM food is probably safe for most of us, it does risk killing a few of us. A while back, someone had the idea to improve the nutritional quality of soybeans by creating a transgenic soybean — borrowing 2S albumin production from Brazil nuts. As it turned out, if you were deathly allergic to Brazil nuts, you would also be deathly allergic to this soybean. Consider the dilemma of someone who fears Brazil nuts. You grow up knowing that you’re deathly allergic to Brazil nuts, and you learn how to avoid them and products that contain them. How would you cope if GM soybeans containing your allergen entered the market, but weren’t labeled as such? Soybeans are everywhere, from baby food to breakfast cereal to McDonald’s hamburgers.

So while a GM soybean is not “substantially different” from non-GM food, that is, while it doesn’t contain weird proteins that we’ve never dealt with, that doesn’t mean it’s such a safe food that it doesn’t require special FDA attention and labeling.

[Richard Caplan, U.S. Public Interest Research group] cites as a major weakness in the report its discussion of the potential allergenicity of genetically engineered crops. While the report authors agree that allergenicity should be evaluated “in every case” and that improvements to the current system are known and have been thoroughly discussed, it fails to call on the FDA to institute a mandatory pre-market assessment according to commonly accepted protocols like the one laid out by the Food and Agriculture Organization and World Health Organization.

U.S. PIRG has long supported a system that requires foods to be labeled if they contain genetically engineered ingredients, which would help to accomplish a recommendation of the report that the government should require that food labels include “relevant nutritional attributes so that consumers can receive more complete information about the nutritional components in GM foods introduced to the marketplace.” The report also calls for a significant increase in transparency of data submissions, which would help remove the large cloud of secrecy surrounding whatever testing is done on genetically engineered crops. For example, a Monsanto study recently reported in Le Monde appears to show deleterious effects on rats in a feeding study of genetically engineered crops, but the company has failed to release it, claiming it as confidential business information.

“The fact is these foods are on our dinner tables right now,” concluded Caplan. “Unfortunately there remains much work to be done to improve the system of oversight for genetically engineered food crops, and it starts by changing the current voluntary system at FDA to a mandatory one.”
– Environmental Media Services

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Republished from South Africa’s Sunday Times of July 25, 2004:

The throw of the genetic dice helps to determine whether you seethe with rage or turn the other cheek, a study suggests.

Researchers have found evidence that some people inherit a genetic make-up that makes them more prone to aggression and violence.

However, the “bad behaviour gene” is only activated if people were neglected or abused as children, scientists say.

The findings add to growing evidence that the “nature versus nurture” debate is too simplistic.

Behaviour is actually influenced by a complex interaction between genes and environment, researchers say.

The research raises the possibility that babies could be screened for genetic mutations that increase the risk of excessive aggression later in life. Scientists may also develop drugs to reduce the risk of violent offending in adolescents and young adults.

Although the study was carried out in monkeys, its findings closely mirror previous research on genes and aggression in humans.

The team, led by Dr Steven Suomi of the National Institute of Child Health and Human Development in Bethesda, Maryland, looked at the links between aggressive behaviour, genes and upbringing in rhesus monkeys.

Between 5% and 10% of wild and captive male rhesus monkeys are extremely violent. They pick fights with the strongest males and turn play fights into bloodbaths.

Suomi split the monkeys into two groups.

Half were deprived of their mothers at birth and reared with their brothers and siblings for the first six months. The rest were reared naturally. The scientists then looked for a gene called 5HTT that has been linked to impulsive aggression.

The gene is involved in the way the brain handles the feel-good chemical messenger serotonin and comes in two varieties – a “short” mutation which leads to low serotonin levels, and a “long” variety leading to higher levels.

The animals that had the short “bad behaviour” version of the gene and who were separated from their mothers developed into ultra-violent monkeys, the researchers found.

However, the short version of the gene had no e ffect on the monkeys’ behaviour if they were raised by their mothers.

“There is a buffering effect of good mothers,” said Suomi. “It is the gene-environment inter action.”

Monkeys with the longer version of the gene were placid, irrespective of whether they were separated from their mothers.

The findings highlight how good parenting can counteract the effects of bad genes.

It also helps to explain why some children grow into well- adjusted, happy and normal adults despite suffering the most appalling traumas.

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As reported here on the Gene Expression blog, the TV execs who brought us some quality TV reality shows like “Big Brother” are bravely venturing where no reality TV show has gone before: into a living body.

The premise of Make Me a Mum is this: 1,000 men, or if you prefer, the sperm of 1,000 men, will be competing with one another for the opportunity to fertilize a single lucky woman’s egg. Were the fertilization to happen the old fashioned way, I think Brighter Pictures (UK) could anticipate great ratings during the climax of the series, at least. But the way this show is being pitched, fertilization will be taking place in vitro, so that the two finalist teaspoons of sperm, tailed by fiberoptic cameras, can battle each other on TV as they try to reach the egg.

Don’t got out and arrange to get a UK TV feed just yet though. Make Me a Mum isn’t likely to get out of concept stage, based on public outrage and broadcaster indifference.

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Source: Gene Expression, reporting on this Daily Mail UK article.

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http://www.fortwayne.com/mld/newssentinel/living/9115937.htm

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Genetic technology, which already has altered our food supply, will soon be used to enhance our muscles and bodies, scientists say. Gene therapy can help rehabilitate patients suffering from muscle-wasting disease such as muscular dystrophy and improve muscle function for the elderly. But it also would inevitably be co-opted and abused by opportunistic athletes. Already, eager early adopters are knocking on the door of University of Pennsylvania genetic researcher H. Lee Sweeney, who has found that combining genetic manipulation with weight training can double muscle strength and speed in rats [Source: Bioethics + Human Dignity / Chicago Tribune]

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News on the cancer-fighting front: Mycobacterium smegmatis (yes, you did correctly guess where we got these fellows!) has been genetically modified to produce a protein which results in the destruction of unwanted cells. Researchers used one of these tricks where you fake out your own immune system by getting it to respond to something you’ve injected, though what you’re really after is attacking the tumor nearby the injection spot.

To date it appears this may be the best way to treat bladder cancer… (8 out of 10 animals had no more tumors after being treated with the GM-bacteria.)
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Source: BBC http://news.bbc.co.uk/2/hi/health/3867331.stm

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Interesting thing, as this article mentions that 1 in 3 new cancers diagnosed each year are skin cancers. (News to me!) Mechanism of function is interesting, as it modifies cell behavior instead of just being a sun shield.

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Scientists are on their way to creating a new generation of sunscreens that boost the skin’s ability to protect itself from skin cancer, with effects that could last for days rather than hours…
More…

[Source: Bioethics + Human Dignity]

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What causes asthma? Is it more common today, or just more diagnosed? Do you get it as a result of living in a big polluted city? Or do you get it by taking too many baths?

HealthDay reports that Asthma [is] Emerging as Genetic Disorder

…A child with one parent who has asthma has a 30 percent chance of developing the airway condition herself. If both parents have it, her odds of getting it approach 70 percent — not a given but a stacked deck.

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If you had been adopted by your parents, would you want to know? If so, at what age? And why? If the answer to the “Why?” question was, “Because I would want to have the opportunity to meet my biological (genetic) parents”, then consider this:

What about babies who come to term as a result of in vitro fertilization? Do they have a right to know how they got here? Does it even matter?

According to this German study, most parents answer “no”.

Parental Attitudes Toward Embryo Donation

Mon Jun 28, 2004 10:12 AM ET

BERLIN (Reuters) – Only about a third of parents whose children were born through embryo donation plan to tell them how they were conceived, scientists said Monday.

Although the parents had the same level of commitment and affection for their children as couples who adopted or had in-vitro fertilization, they preferred to keep silent because of concerns about how the child would react.

“The most common reasons for not telling the child about their method of creation were fears that it would upset the child or damage family relationships,” Fiona MacCallum told a fertility conference.

There was also a feeling, she said, that since the mother carried and gave birth to the child, she was the real mother and there was no need to tell the child anything different.

The research psychologist at City University in London questioned 21 couples whose children had been conceived through embryo donation, 28 who had adopted and 30 who had in-vitro fertilization.

Although women who become pregnant through embryo donation give birth to their children, like adoptive parents they have no genetic link to them.

All the parents were interviewed and completed questionnaires when their children were between 2 and 5 years old.

Embryo donation parents scored higher in emotional over-involvement, which includes traits such as putting the needs of the child over other family members or a reluctance to use babysitters or care-givers, but there was no difference in the quality of parenting between the three groups.

“This supports the idea that it is the level of commitment to parenting that is important, and not the presence or absence of biological links between parents and children,” MacCallum added.

The findings were presented during a meeting in Berlin of the European Society of Human Reproduction & Embryology.

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