The genes (code sequences stored in the DNA) are not modified.

Epigenetics is a recent discovery that the genes can be muted or not expressed).

The mechanism is that parts of the DNA strand often curl themselves up in a ball which prevents themselves from being replicated/expressed. Researchers are discovering there are many factors that influence this behavior.

I think it’s better to describe methylation as up or down regulation.

"While our genes are not changed by life experiences, they can be tuned through a system known as epigenetics."

It is indeed not a modification of the genetic code. And the transmission of epigenetic state from one generation to the next is much less straightforward.

The article says this.

  But there is another lasting effect of the attack, hidden deep in the genes of
  Syrian families. The grandchildren of women who were pregnant during the siege — 
  grandchildren who never experienced such violence themselves — nonetheless bear 
  marks of it in their genomes. Passed down through their mothers, this genetic
  imprint offers the first human evidence of a phenomenon previously documented
  only in animals: The genetic transmission of stress across multiple generations.

The article clearly implies a modify of the genes. The genome is altered.

The actual study doesn’t make that claim, the article is presenting it incorrectly. They’re talking about a methylation on certain genes. Think of it as amplification or attenuation and of a signal. The signal is the same, just weaker or stronger.

I've read the article, I've read the comments. Nobody has remotely tried to explain how these changes are heritable, at all. The article had an image with the word "germline", which was never expounded on.

The press release writer was a bit shit at understanding basic scientific jargon. The research only finds epigenetic markers. There are no genetic changes. There are detectable changes to gene expression, and that's it.

So why do we discuss genes if we actually mean heritable traits? Scientists should probably take the lead in abandoning "gene" as a generally useful concept outside of their field.

The article doesn't really explain it, but looking at the image provided, I think I understand. A girl is born with all her eggs already, so the egg germ cell that becomes the grandchild is already present inside the grandmother while she is pregnant with the mother. In this case, the genes being methylated are in the cell which will go on to become the grandchild. Changes themselves are not being passed down through generations, per se, but are being effected in the 3rd generation at the instant of the trauma itself.

I'm also very skeptic of the way these affirmations are made. Other studies I've read boil down to epigenetic changes caused by stress, not actual DNA rewriting, otherwise it wouldn't go back to normal ever. In other words, these epigenetic changes are directly proportional to how stressful the environment remains.

The article mentions Hama, where a massacre occurred, and 40 years later the inhabitants still show epigenetic changes caused by stress. Surely the environment still being stressful is more to blame than their ancestor's genetic memory.

There's great danger of misinterpreting this kind of research to bolster ideological agendas. I've seen this misused as "my grandpa was a victim of the holocaust, so I, born into and living a comfortable and peaceful life, am also a holocaust victim and deserve respect".

I'm not a biologist either, but from my reading there are many cellular elements that influence genetic expression that are not encoded in DNA. And those elements can mutate as a result of the individual's experience during their lifetime. Some of them have independent genetic lines. DNA = behavior is reductive.

To a very minor degree. If DNA is a compiled binary, epigenetics is like the settings database. It can toggle and alter behaivor and it has some degree of persistence, but ultimately it can only change things in ways allowed by the binary.

Maybe Darwinian evolution has the intrinsic tendency to evolve Lamarckian heredity mechanisms.