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Comment by bwblabs | Hacker News Reader

Article is based on Self-control forecasts better psychosocial outcomes but faster epigenetic aging in low-SES youth (http://www.pnas.org/content/early/2015/07/08/1505063112.full...), someone with access who can check N and the significance of change of the groups?

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Given the data found on this chart http://cdn.static-economist.com/sites/default/files/imagecac... (which shows more than a hundred of points, quite good compared to the size of the sample : “almost 300 black American teenagers”), I'm really sceptical about the relevance of the results …

I think it's The Economist's visualization that is confusing, not the data. I read the paper, they have 292 subjects. Here's the Tukey plot (which to me, is less confusing than the scatter plot) from the paper on age in low and high self-control groups: http://imgur.com/ijL6nrp

Also, according to the authors, 'skin-deep' metrics improved: http://imgur.com/lXD3f2L

One of those rare cases where the paper title explains the phenomenon better than the article. If this is based on DNA-methylation, does that mean the 'damage' is heritable?

You seem to be asking whether epigenetic traits are inheritable. It will take a while for the scientific community to fully accept this since it smells of Lamarckism, but if we do not accept transgenerational epigenetic transmission it gets really hard to explain things like this: http://phenomena.nationalgeographic.com/2013/12/01/mice-inhe...

Yes, there has been some recent studies that suggest the Central Dogma [1] may not apply in all cases. If I remember correctly, some forms of DNA methylation is heritable on the male side. Disclaimer: not a molecular biologist.

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

From a quick scan of the article the chart is based on figure 1. p-value for the more disadvantaged group is 0.017 for the less disadvantaged it's 0.02. There's a 3rd group, 'medium disadvantaged', which has a horizontal line.

The trend is more obvious when the points for the individual groups are separated out, but it does seem to me that a small number of points at the extremes might account for slope - if you removed one or two key points from each group the slopes might go away.

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