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How much a baby is touched leaves measurable effects on DNA methylation (2017)

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Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#31

Post by dwaltrip »

08-15 wrote: post #25

Even if this result is real (I smell bad statistics), it's completely useless. All cells in our bodies have the same genome. But a hepatozyte and a neuron are very different cells, aren't they? The difference is that cells specialize, and they do so by selectively methylating their genome (not the only mechanism, but an important one), thereby modifying the expression of genes. So a liver has a very different epigeno…

Can you back up your implication that the saliva epigenome has no other meaningful and impactful correlates?

Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#32

Post by crawfordcomeaux »

amelius wrote: post #13
crawfordcomeaux wrote: post #8

Earlier quoted context omitted.

The article is talking about methylation, which I always interpret to mean they're referring to the epigenome. It doesn't change our DNA, so much as the expression of it.

How much state is in the expression of DNA? Will all this type of state be lost eventually, or is there also persistent state in the expression of DNA?

Epigenetic markers that appeared during the potato famine and Great Depression have been found in grandchildren of those who lived it.

There's also evidence healing from trauma can change expression.

What do you mean by persistent state?

Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#33

Post by objektif »

dcolkitt wrote: post #20
aidenn0 wrote: post #11

Earlier quoted context omitted.

There are issues with twin studies, not the least of which the number of twins raised separately, but not adopted, is tiny. However adoptive parents are a small self-selected subset of the population.

Most twin studies simply compare identical and fraternal twins in non-adopted households. Since identical twins share twice the genetic covariance of fraternal twins, the impact of family environment can be backed out from the respective intra-pair correlation coefficients. In the limit case if genetics played no factor, then fraternal and identical twins should have identical pairwise correlations. For example suppo…

Why would parents of twins pay much more attention to one than the other?

Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#34

Post by getpost »

glofish wrote: post #3

I think there is a high chance that is 100% bullshit. Most likely has to do with confusing cause-and-effect. It could be just as well that highly methylated babies cry more and could be more demanding or parents with highly methylated babies are themselves less tolerant to crying thus end up handling babies more. The problem, they way it is being reported, and they way it lines up with pseudo-scientific mumbo-jumbo g…

>I think there is a high chance that is 100% bullshit.

I haven't read the paper this article is based on, so I can't comment on the study or the reliability of the results.

However, epigentic effects related to the degree of maternal touch have been convincingly demonstrated in naked mole rats in crossover studies. I posted about this research previously. (https://news.ycombinator.com/item?id=18749285)

Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#35

Post by glofish »

mindfulhack wrote: post #21
glofish wrote: post #3

I think there is a high chance that is 100% bullshit. Most likely has to do with confusing cause-and-effect. It could be just as well that highly methylated babies cry more and could be more demanding or parents with highly methylated babies are themselves less tolerant to crying thus end up handling babies more. The problem, they way it is being reported, and they way it lines up with pseudo-scientific mumbo-jumbo g…

I'm not a professional scientist, but shouldn't the spirit of science be curiosity and exploration at all times, not shooting down a new idea as soon as you hear it? If such an attitude were present in every person, science would not progress at all. I'm not that long a veteran here, but I think at HN we are more interested in having our minds and ears open and feeling we can comfortably share and discuss articles th…

This is about junk science - that is the true danger and bottleneck to science - that reward for making unsubstantiated but grandiose claims. These do far more damage than potentially unfair criticism.

I am a scientist by profession and I have come to believe that the majority of work in this field is wasted because people chase that 5-minute fame. Once you are in the field you can smell the stink a mile away.

It always sounds the same: "A second genetic code discovered", "Touch reflected in the DNA", "Next cure for cancer", "Scientists can edit now genes at high fidelity with CRISPR" all pure bullshit.

Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#36

Post by aidenn0 »

tomrod wrote: post #23
anbop wrote: post #17

Earlier quoted context omitted.

Adoptive parents are people who have gone through a lot of effort and expense to get their children, so they're far more likely to be heavily invested in their kids. It's also expensive so they're likely to have money. If the effects of parenting are strong, but "cap out" -- i.e. above a certain level of care, parenting does little, but before that level it has a strong effect -- then twin studies will show little of…

I'm not sure I follow the causality argument here. A twin study should normalize everything genetically. Ergo epigenetic expression and environment are the only two causal levers. It sounds like you're arguing that parental involvement has a causal impact, which is the point of the studies to a degree. Perhaps my original question was unclear: is there something the twins do or have done to them that cause a latent s…

We are questioning how much the parenting has an affect on the child. The parents are self-selected and so are more likely to be similar to each other.

Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#37

Post by hornetblack »

dmos62 wrote: post #28

So, just how mutable is the DNA? For the sake of the discussion, I don't know anything about DNA that I can say I didn't get from a sci-fi flick.

There's a special thing called "Epigenetics". The genes coded in DNA don't change. But how they're used can change.

There's methyl groups that attach to the DNA. These stop parts of the DNA being read.

There's Histones which wind up your DNA and control how much can be read.

These are used control which parts of DNA are used by which cells. Evey cell has the same Genome, but each cell needs a different program to function, so changing the Gene Expression you get a different kind of cell.

Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#38

Post by glofish »

heimatau wrote: post #18
glofish wrote: post #16

Earlier quoted context omitted.

I have performed DNA studies in my career. Measuring and interpreting methylation - understanding what it is, why, when and where it is present is at its infancy at best. Sadly I have prime view how clickbaity ideas like this one drive most of the motivations behind investigations in life sciences. It is not just this paper that is bullshit, the whole field of "epigenetics" that this paper is a representation of is b…

> is at its infancy at best. Hence why the main source is published with ~90 subjects studied. Science starts with one paper/experiment and builds from there. > The lie is not that A and B are present at the same time. The lie is presenting story as if A was caused by B. There is absolutely no evidence for that. That's not a lie. It's called a hypothesis. It's testable. They've tested it and encourage others to test…

I will tell you what they did. They collected data, with no hypothesis or any idea what they are looking for, then desperately fit various models until something showed up as statistically significant.

Of course, you could say: how dare you, how would you even know, ... I work in this field, the p-hacking, harking (hypothesizing after the results are known) is both pervasive and endemic. they massaged the factors, the genders, the ethnicity, the socioeconomic status etc until the model did something that was publishable.

It simply not possible to accurately correlate these two measures: self-reported minutes of touching a baby with the methylation levels of the DNA of that baby - if you are serious about accounting for all the possible variations across all factors

Re: How much a baby is touched leaves measurable effects on DNA methylation (2017)

#39

Post by m3kw9 »

glofish wrote: post #3

I think there is a high chance that is 100% bullshit. Most likely has to do with confusing cause-and-effect. It could be just as well that highly methylated babies cry more and could be more demanding or parents with highly methylated babies are themselves less tolerant to crying thus end up handling babies more. The problem, they way it is being reported, and they way it lines up with pseudo-scientific mumbo-jumbo g…

I think they forgot to say being more touched probably means parents are more close by, more caring. Why would you not touch a baby if you are constantly close by? So probably not BS, just a study say is right, but not for all the right reasons.
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