Are our genes triggered by environmental factors?

Question

I read this recently and was intrigued:

"Now biology is heading in the same direction. The models we were taught in school about "dominant" and "recessive" genes steering a strictly Mendelian process have turned out to be an even greater simplification of reality than Newton's laws. The discovery of gene-protein interactions and other aspects of epigenetics has challenged the view of DNA as destiny and even introduced evidence that environment can influence inheritable traits, something once considered a genetic impossibility."

Can someone point me in the right direction to read more about this?

Answer 1

yes, a great many human traits are multifactorial in that their manifestation is subject to both genetic and environmental factors.

we are much more connected to our environment that previously thought.

Answer 2

Johns Hopkins researchers who studied the genomes of people in Iceland and Utah say they may have found a clue to why people are increasingly prone to disease as they age.

The answer may not lie specifically in the person's genes, but in chemical changes occurring around the genes that help determine which are active and which are silent.

As a result, a person could become more prone to heart disease, cancer and other diseases of aging because certain genes that used to function no longer do so - or vice versa. Animal studies have shown that such changes can be triggered by environmental forces such as diet.

Methylation of DNA is involved.

Answer 3

Absolutely your genes can be turned on or off depending on environmental factors.  One study (I can't remember if it was in Norway or Sweden or . . .) found that what people's grandparents were subjected to for diet affected whether certain genes were expressed in them.  There is also evidence in mice that turning on/off genes is directly related to obesity.  They are also following the genomes of identical twins and discovering that as they age (and are therefore exposed to minor differences in environment), their epigenome changes more and more from each other.

The best popular media I've seen on epigenetics is the NOVA show "Ghost in your Genes".  You can see parts of it and read the transcript for free at: http://www.pbs.org/wgbh/nova/genes/  If you're really interested in it, I suggest trying to catch the show on PBS.