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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)

#11

Post by aidenn0 »

dcolkitt wrote: post #6
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…

One thing that we know from decades of twin studies is that childhood family environment explains a vanishingly small percent of long-run adult outcomes. Contextualizing this single study's result against the much larger, more established evidence from twin studies strongly suggests that one or more of the following is true. - The results are spurious and won't replicate. - The results are true, but the association i…

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.

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

#12

Post by tomrod »

aidenn0 wrote: post #11
dcolkitt wrote: post #6

Earlier quoted context omitted.

One thing that we know from decades of twin studies is that childhood family environment explains a vanishingly small percent of long-run adult outcomes. Contextualizing this single study's result against the much larger, more established evidence from twin studies strongly suggests that one or more of the following is true. - The results are spurious and won't replicate. - The results are true, but the association i…

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.

It's not vanishingly tiny, simply small.

Can you think of a reason selection bias could be an issue, thus invalidating twin study cohorts?

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

#13

Post by amelius »

crawfordcomeaux wrote: post #8
BurningFrog wrote: post #7

Wait... Does our DNA change as we age?? If so, to only sample the DNA after the study and not before seems crazy.

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?

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

#14

Post by Xixi »

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?

The field of study is called Epigenetics [1]. I know practically nothing about it, but it seems that some of these alterations to the expression of DNA are not only persistent, but can also be inherited. Which is why some of these discoveries have been called a revenge of Lamarck over Darwin...

[1] https://en.wikipedia.org/wiki/Epigenetics

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

#15

Post by glofish »

tribler wrote: post #5
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…

scientific study: "The importance of touch in development", Brain Research Centre and Department of Psychology, University of British Columbia, Vancouver. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2865952/#__ffn_... (as commented elsewhere)

most certainly, I would fully agree that touch is an important ingredient to socialization and stimulation -

it is the premature claim that it changes DNA what is so annoying and misleading.

because once something changes your DNA it suggests that it is there forever (that is why it captures people's imagination)

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

#16

Post by glofish »

heimatau wrote: post #9
tribler wrote: post #5

Earlier quoted context omitted.

scientific study: "The importance of touch in development", Brain Research Centre and Department of Psychology, University of British Columbia, Vancouver. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2865952/#__ffn_... (as commented elsewhere)

That study is only reference to the existing consensus, not the actual study from the OP. I don't have the time to dig out the actual study but it looks like [1] it's originating in Canada (not NIH/USA) based on the publication of the press release. Original comment of thread doesn't understand how much research is behind this idea (touch linked to higher outcomes long-term). I'd strongly recommend the commenter to r…

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 bullshit as well - this paper is just one out of the long line.

As I pointed out it there is simply no proof that handling changes DNA. It could just as well handling stimulates the development rate which, in turn, also shows up as another signal.

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.

Now hundreds of scientists want a piece of the "cool" story, will jump headfirst into proving how LOVE will reflect in the DNA. No one will care about understanding what the heck is methylation - they will all be chasing baby handling and methylation. That's what I have seen happening and will keep happening thanks to papers like this.

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

#17

Post by anbop »

tomrod wrote: post #12
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.

It's not vanishingly tiny, simply small. Can you think of a reason selection bias could be an issue, thus invalidating twin study cohorts?

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 that effect.

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

#18

Post by heimatau »

glofish wrote: post #16
heimatau wrote: post #9

Earlier quoted context omitted.

That study is only reference to the existing consensus, not the actual study from the OP. I don't have the time to dig out the actual study but it looks like [1] it's originating in Canada (not NIH/USA) based on the publication of the press release. Original comment of thread doesn't understand how much research is behind this idea (touch linked to higher outcomes long-term). I'd strongly recommend the commenter to r…

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 as well.

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

#19

Post by baxtr »

dcolkitt wrote: post #6
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…

One thing that we know from decades of twin studies is that childhood family environment explains a vanishingly small percent of long-run adult outcomes. Contextualizing this single study's result against the much larger, more established evidence from twin studies strongly suggests that one or more of the following is true. - The results are spurious and won't replicate. - The results are true, but the association i…

I don’t know. I have read this before. But this goes so much against my gut feeling and what I have experienced that it is hard to believe. It’s counter intuitive to say the least.

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

#20

Post by dcolkitt »

aidenn0 wrote: post #11
dcolkitt wrote: post #6

Earlier quoted context omitted.

One thing that we know from decades of twin studies is that childhood family environment explains a vanishingly small percent of long-run adult outcomes. Contextualizing this single study's result against the much larger, more established evidence from twin studies strongly suggests that one or more of the following is true. - The results are spurious and won't replicate. - The results are true, but the association i…

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 suppose pairs of identical twins have 45% pairwise correlation for adult IQ. And say fraternal twins have 25% correlation for the same measure. That would tell us that the population level variance of adult IQ is 40% attributable to genetic heritability, 5% to environmental heritability , and 55% to non-heritable factors (i.e. not genetics and not family environment).

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