5 ms·

Scientists say they have new evidence that autism begins in the womb

25 points by rb2e 13y ago

dispense 13y ago
Patches of Disorganization in the Neocortex of Children with Autism http://www.nejm.org/doi/full/10.1056/NEJMoa1307491 http://www.nejm.org/doi/full/10.1056/NEJMoa1307491 doi://10.1056/NEJMoa1307491 Background Autism involves early brain overgrowth and dysfunction, which is most strongly evident in the prefrontal cortex. As assessed on pathological analysis, an excess of neurons in the prefrontal cortex among children with autism signals a disturbance in prenatal development and may be concomitant with abnormal cell type and laminar development. Methods To systematically examine neocortical architecture during the early years after the onset of autism, we used RNA in situ hybridization with a panel of layer- and cell-type–specific molecular markers to phenotype cortical microstructure. We assayed markers for neurons and glia, along with genes that have been implicated in the risk of autism, in prefrontal, temporal, and occipital neocortical tissue from postmortem samples obtained from children with autism and unaffected children between the ages of 2 and 15 years. Results We observed focal patches of abnormal laminar cytoarchitecture and cortical disorganization of neurons, but not glia, in prefrontal and temporal cortical tissue from 10 of 11 children with autism and from 1 of 11 unaffected children. We observed heterogeneity between cases with respect to cell types that were most abnormal in the patches and the layers that were most affected by the pathological features. No cortical layer was uniformly spared, with the clearest signs of abnormal expression in layers 4 and 5. Three-dimensional reconstruction of layer markers confirmed the focal geometry and size of patches. Conclusions In this small, explorative study, we found focal disruption of cortical laminar architecture in the cortexes of a majority of young children with autism. Our data support a probable dysregulation of layer formation and layer-specific neuronal differentiation at prenatal developmental stages. (Funded by the Simons Foundation and others.)
- neolefty 13y ago
  Thank you for posting that! I am not exposed to current research on autism, but I want to know what is happening. Does that mean that autism can be an evolutionary symptom of trying to balance maximum intelligence (which I assume requires, in layman's terms, a ton of neurons) with robust brain organization and overall brain health? And do we know if any other species experience autism?
  - deleted 13y ago
    [deleted]
thaumasiotes 13y ago
Coming soon: new evidence that prostate cancer begins in the womb. new evidence that schizophrenia begins in the womb. new evidence that Alzheimer's begins in the womb.
- zxcdw 13y ago
  Is this supposedly amusing or are you just venting off because of something, with no intent of contributing to any form of civilized discussion?
  - thaumasiotes 13y ago
    It's not really interesting that a condition which is with you from birth might begin in the womb. The others I listed are also known to be... phrased conservatively... strongly influenced by something in the womb, but at least they all exhibit late-life onset and could conceivably begin at some later point.
    - neolefty 13y ago
      The headline is really just a teaser in this case. The meat of the article is more about how autism begins, and how some of the critical developmental steps that lead to autism occur in the womb. The other conditions (prostate cancer, for example) are much more significantly influenced by events that take place well after birth.
      - thaumasiotes 13y ago
        Prostate cancer is one of the poster children for the theory "the death rate from cancer is increasing because people have stopped dying of other things before they inevitably get cancer". Far and away the most significant influence on whether you have prostate cancer is whether you have a prostate gland; this is determined in the womb. In the depressing words of my mom's medical school professor, having a prostate gland is sufficient to develop prostate cancer; the prevalence is 100% (of males). The question (assuming what you're really worried about is mortality) is not "do I have prostate cancer?" -- you do. The question is "how badly is my prostate cancer growing?"

25 points by rb2e 13y ago

Patches of Disorganization in the Neocortex of Children with Autism http://www.nejm.org/doi/full/10.1056/NEJMoa1307491 http://www.nejm.org/doi/full/10.1056/NEJMoa1307491 doi://10.1056/NEJMoa1307491 Background Autism involves early brain overgrowth and dysfunction, which is most strongly evident in the prefrontal cortex. As assessed on pathological analysis, an excess of neurons in the prefrontal cortex among children with autism signals a disturbance in prenatal development and may be concomitant with abnormal cell type and laminar development. Methods To systematically examine neocortical architecture during the early years after the onset of autism, we used RNA in situ hybridization with a panel of layer- and cell-type–specific molecular markers to phenotype cortical microstructure. We assayed markers for neurons and glia, along with genes that have been implicated in the risk of autism, in prefrontal, temporal, and occipital neocortical tissue from postmortem samples obtained from children with autism and unaffected children between the ages of 2 and 15 years. Results We observed focal patches of abnormal laminar cytoarchitecture and cortical disorganization of neurons, but not glia, in prefrontal and temporal cortical tissue from 10 of 11 children with autism and from 1 of 11 unaffected children. We observed heterogeneity between cases with respect to cell types that were most abnormal in the patches and the layers that were most affected by the pathological features. No cortical layer was uniformly spared, with the clearest signs of abnormal expression in layers 4 and 5. Three-dimensional reconstruction of layer markers confirmed the focal geometry and size of patches. Conclusions In this small, explorative study, we found focal disruption of cortical laminar architecture in the cortexes of a majority of young children with autism. Our data support a probable dysregulation of layer formation and layer-specific neuronal differentiation at prenatal developmental stages. (Funded by the Simons Foundation and others.)

neolefty 13y ago
Thank you for posting that! I am not exposed to current research on autism, but I want to know what is happening. Does that mean that autism can be an evolutionary symptom of trying to balance maximum intelligence (which I assume requires, in layman's terms, a ton of neurons) with robust brain organization and overall brain health? And do we know if any other species experience autism?
- deleted 13y ago
  [deleted]

thaumasiotes 13y ago

Coming soon: new evidence that prostate cancer begins in the womb. new evidence that schizophrenia begins in the womb. new evidence that Alzheimer's begins in the womb.

zxcdw 13y ago
Is this supposedly amusing or are you just venting off because of something, with no intent of contributing to any form of civilized discussion?
- thaumasiotes 13y ago
  It's not really interesting that a condition which is with you from birth might begin in the womb. The others I listed are also known to be... phrased conservatively... strongly influenced by something in the womb, but at least they all exhibit late-life onset and could conceivably begin at some later point.
  - neolefty 13y ago
    The headline is really just a teaser in this case. The meat of the article is more about how autism begins, and how some of the critical developmental steps that lead to autism occur in the womb. The other conditions (prostate cancer, for example) are much more significantly influenced by events that take place well after birth.
    - thaumasiotes 13y ago
      Prostate cancer is one of the poster children for the theory "the death rate from cancer is increasing because people have stopped dying of other things before they inevitably get cancer". Far and away the most significant influence on whether you have prostate cancer is whether you have a prostate gland; this is determined in the womb. In the depressing words of my mom's medical school professor, having a prostate gland is sufficient to develop prostate cancer; the prevalence is 100% (of males). The question (assuming what you're really worried about is mortality) is not "do I have prostate cancer?" -- you do. The question is "how badly is my prostate cancer growing?"