Genes and Lifestyle


The best things- come in little- packages
Barked: Mon Jul 23, '07 9:49am PST 
I saw this on GMA this morning and thought of you guys. I know some of you guys have similar conditions as your grandparents such as allergies. I also know a lot of people here study genes. What do you guys think about this story:

Lifestyle, Not Just Genes, Could Imprint Next Generation
Research Suggests Appearance May Not Be All That's Passed Down From Grandparents
July 23, 2007 —

People can inherit baldness, facial features and other physical traits from their grandparents. Some even believe musical abilities and rhythm can be passed from previous generations.

But according to researchers, it's not just your grandparents' genes leaving their imprints on you, but also their lifestyle factors.

Researchers in the science of epigenetics looked at how things like diet and physical activity can alter a person's genes, not just for him or her but also future generations.

"There is now very good evidence that our grandparents can predispose to disease in subsequent generations," said Mark Hanson of Southampton University. "That comes both from laboratory studies in small animals like rats and mice, and it also comes from population studies in humans."

In addition, University of Southern California doctors found women who smoked during pregnancy not only increased their child's risk of asthma, but also their grandchildren's chances, too. The research suggested tobacco may damage the fetus  and if the baby is a girl, her eggs or the DNA may be affected. It could alter immune function, thus increasing her risk of asthma.

There are plenty doctors who said the theory is intriguing, but it's still theory because the research on the human link is far from proven.

"There are some interesting early data that would be along those lines in experimental animals," said Dr. Andy Feinberg, of Johns Hopkins University. "So far in humans, this is an area that is interesting speculation but too early to say."

Despite that, researchers in epigenetics suggest, while our lifestyles have changed dramatically, our genes have not.

"We've changed our world in our lifetime in the kinds of food we eat, the use of elevators," Hanson said. "We sit at home & a playing computer game rather than going out for a cycle ride. All of those things have changed enormously."

The end result could be a genetic mismatch that wreaks havoc with our bodies and future generations. It could explain the explosion of certain lifestyle-induced diseases like obesity, diabetes and heart disease.

Researchers stressed the importance of healthy habits early for the sake of future generations.

"If we pay more attention to getting young adults, who will be parents and eventually grandparents, getting them healthier and getting them to understand this problem," Hanson said, "then we'll be able to reduce the risk of the burden, we should say, of these diseases in subsequent generations."

Copyright © 2007 ABC News Internet Ventures

I am currently working for a study that is studying the role of genetics in heart disease in American Indians. If the theories in this article are true, it seems more important than ever to stress lifestyle changes in reducing health disparities.

A Doggie Scholar
Barked: Tue Jul 24, '07 11:12am PST 
Makes sense, I think... I also think that what child inherits much much more from his/her parents than just health stuff....

Have you guys seen this British documentary called "Seven Up"? It was a project that went over for decades, and the director pretty much picked 14 kids that represent different class/race/background, and interviewed them every 7 years. They were first interviewed when they are 7, and the documentary follows them until they are middle aged. What's evident after watching the entire series (each interview every 7 years is an episode) is that... the values and the goals and the direction in life that the parents instill in their childre by age 7 pretty much carries them through their entire life. Even if you rebel and do your thing at your teen years/early tweens, they seem to go right back on track afterwards. It's a frightening thought, but I think it also completely emphasizes that parenting shouldn't be done on a whim.
Sabrina- 2000~2012

To break- injustice we- must break- silence
Barked: Sat Aug 25, '07 7:34am PST 
This actually makes a lot of sense. There are regions of your DNA that become supercoiled and so unactive, and other regions that stay pretty uncoiled so that the genes in those regions can be transcribed a lot. Often regions that are supercoiled remain so when they passed on, at least in organisms like yeast or bacteria (can't remember which organism it was that I studied this in). Therefore it could be that a predisposition for a region of DNA to be supercoiled (and so transcribed, or turned into proteins less), which might be something that occurrs as a result of the environment, could theoretically be passed on to your offspring.

Of course with human reproduction this does bring up some intresting questions-- I mean with guys, they produce sperm throughout their entire lifetime so it makes sense that changes to a mans DNA during his lifetime can be passed on to his offspring. However for women, all the eggs we will ever release in our life are already arrested in the middle of meiosis by the time we're about 6 months along in the womb.

However, the research I read about this sort of thing didn't take into account weather the supercoiled regions that were inherited were kept like that due to a structural change or due to some protein in the cytoplasm that enforced such a change. It would be very likely, especially in women, that in the egg there could be lots of proteins from the mom that would dictate which regions of DNA would be supercoiled and which wouldn't. Of course this wouldn't apply quite as much for sperm, since they are mostly just DNA and a casing and don't have hardly any other proteins from their progenitor cell's cytoplasm.