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No mention of twin studies? The article doesn't appear to distinguish between genes as unit of inheritance and heritability of traits which many studies seem to

No mention of twin studies? The article doesn't appear to distinguish between genes as unit of inheritance and heritability of traits which many studies seem to indicate is quite significant.

petermcneeley 8y ago
I think its common to focus on the similarity of identical twins. But I actually think the variance in identical twins is far more interesting because it suggests something very radical about the role of development in the non biological sphere. I can give you one example that gave me pause and you should know. At the EAC cafe there were twin kitchen staff. However one was lean and the other was more tubby. Unless there was a transcription issue in the gene for metabolism I think there were identical genes at play. Thus the resulting variance is non biological developmental. There are tons of other anecdotal observations I have made in my experience with identical twins. I think any variance (assuming perfect cloning) suggests something that is non biologically determined.
- SamReidHughes 8y ago
  That variance is partly biological: randomness in early development, genetic differences between identical twins, exposure to pathogens and immune response at an early age, and with women, X chromosome mosaicism. A big sign of this is that if one identical twin is gay, the other is still usually not gay.
- mattnewport 8y ago
  Hey Peter! Twin studies are one of the more powerful tools we have to try and separate out the effects of genetics, shared environment and non shared environment in humans. Shared environment represents what twins raised in the same household have in common in their environment and non shared environment what is still different. Studies of heritability tend to indicate for many traits that genetics have the largest role and (perhaps surprisingly) non shared environment the next largest with shared environment having the smallest (though often still important) role to play. Your example of the twins would be a classic case of non shared environmental influence. Certainly nobody claims that environmental influences are not important and like most things the details are complicated and leave much room for debate over the exact role of each component in determining traits. In some ways it is true that the environmental factors are the most interesting since they are the ones we have most control or at least influence over for ourselves and our children.
- feanaro 8y ago
  > Unless there was a transcription issue in the gene for metabolism I think there were identical genes at play. Thus the resulting variance is non biological developmental. This conclusion is incorrect. The variance was perhaps not due to genetics, but it would be really strange if it wasn't biological.
  - SamReidHughes 8y ago
    Well obviously it's partly non biological. For example, I weighed 52 pounds more several years ago compared to Monday morning. The reason for this disparity is social and psychological.

No mention of twin studies? The article doesn't appear to distinguish between genes as unit of inheritance and heritability of traits which many studies seem to indicate is quite significant.

petermcneeley 8y ago

I think its common to focus on the similarity of identical twins. But I actually think the variance in identical twins is far more interesting because it suggests something very radical about the role of development in the non biological sphere. I can give you one example that gave me pause and you should know. At the EAC cafe there were twin kitchen staff. However one was lean and the other was more tubby. Unless there was a transcription issue in the gene for metabolism I think there were identical genes at play. Thus the resulting variance is non biological developmental. There are tons of other anecdotal observations I have made in my experience with identical twins. I think any variance (assuming perfect cloning) suggests something that is non biologically determined.

SamReidHughes 8y ago
That variance is partly biological: randomness in early development, genetic differences between identical twins, exposure to pathogens and immune response at an early age, and with women, X chromosome mosaicism. A big sign of this is that if one identical twin is gay, the other is still usually not gay.
mattnewport 8y ago
Hey Peter! Twin studies are one of the more powerful tools we have to try and separate out the effects of genetics, shared environment and non shared environment in humans. Shared environment represents what twins raised in the same household have in common in their environment and non shared environment what is still different. Studies of heritability tend to indicate for many traits that genetics have the largest role and (perhaps surprisingly) non shared environment the next largest with shared environment having the smallest (though often still important) role to play. Your example of the twins would be a classic case of non shared environmental influence. Certainly nobody claims that environmental influences are not important and like most things the details are complicated and leave much room for debate over the exact role of each component in determining traits. In some ways it is true that the environmental factors are the most interesting since they are the ones we have most control or at least influence over for ourselves and our children.
feanaro 8y ago
> Unless there was a transcription issue in the gene for metabolism I think there were identical genes at play. Thus the resulting variance is non biological developmental. This conclusion is incorrect. The variance was perhaps not due to genetics, but it would be really strange if it wasn't biological.
- SamReidHughes 8y ago
  Well obviously it's partly non biological. For example, I weighed 52 pounds more several years ago compared to Monday morning. The reason for this disparity is social and psychological.