Evidence for evolution of a key autism-linked gene

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DevilInside
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26 Dec 2010, 5:00 am

btw, have you thought about the currently affordable alternative? get as many spectrumites as you can find to get one of those SNP tests done offered by companies like 23andme (the 99$ sale for this year is over unfortunately, i am looking forward to seeing if i have any autism-linked SNP's in there) atleast that will give you some info on the frequency of certain SNP's while full genome sequences is not yet available to the public. And you could see if these SNP's were common variants in the neanderthal specimens



DevilInside
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26 Dec 2010, 5:29 am

there is no requirement for mental retardation for an autism diagnosis, although there is a requirement of NO mental retardation for asperger's, however, that does not imply that autistics are generally more linked to mental retardation overal. (i can give you the papers i talked about in the other thread which suggested that if you exclude verbal comprehension ability, most people with so called LFA actually perform very well on tests of general intelligence (5% ret*d range, 33% 90th percentile, majority (number not stated in paper unfortunately, 50th percentile or more). So forgive me if this particular assumption/suggestion is particularly offensive to me.



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26 Dec 2010, 6:41 am

DevilInside wrote:
there is no requirement for mental retardation for an autism diagnosis, although there is a requirement of NO mental retardation for asperger's, however, that does not imply that autistics are generally more linked to mental retardation overal. (i can give you the papers i talked about in the other thread which suggested that if you exclude verbal comprehension ability, most people with so called LFA actually perform very well on tests of general intelligence (5% ret*d range, 33% 90th percentile, majority (number not stated in paper unfortunately, 50th percentile or more). So forgive me if this particular assumption/suggestion is particularly offensive to me.


OK. Sorry for being offensive. I assure you that I do not think that all people with autism diagnosis are "mentally ret*d" (whatever that means). I know this is not the case because I have a daughter with the "Autistic syndrome" diagnosis that is not mentally ret*d. She has comorbid Dyslexia and is generally too perfectionist and thus does poorly on verbal IQ-tests.

The issue is that people that are diagnosed with Autism sometimes do not score highly on the personality-dimension (Aspie-quiz), and I'd except some of them to be misdiagnosed as well.

But, ok, I'll settle with getting "Very likely Aspie" on Aspie-quiz, regardless of diagnosis and other issues.



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26 Dec 2010, 6:58 am

DevilInside wrote:
btw, have you thought about the currently affordable alternative? get as many spectrumites as you can find to get one of those SNP tests done offered by companies like 23andme (the 99$ sale for this year is over unfortunately, i am looking forward to seeing if i have any autism-linked SNP's in there) atleast that will give you some info on the frequency of certain SNP's while full genome sequences is not yet available to the public. And you could see if these SNP's were common variants in the neanderthal specimens


Interesting. The test seems to cost $199 today. I wonder how to go about to find which of these SNPs are diagnostic of Neanderthal inheritance? There are quite a few promising ones that I'd like to know (like developmental Dyslexia). I also wonder if they could provide an easy list of reference genome positions for the SNPs they test for as well as a simple result in a file or something in order to easily match. Well, I'd simply have to mail them about this.



DevilInside
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26 Dec 2010, 7:05 am

yes, 23and me allows direct download of your raw SNP data, there are a few third-party applications that use this SNP data to generate their own results. you can find the reference SNP position in dbSNP or through the result of one of the third-party apps which get their SNP frequency info from that database i believe. Now i looked at your link of the neanderthal genome, could you tell me which damn files are actually relevant to the actual genome sequence? there are a shedload of differen files on there with no indication of which is which. this is why i prefer NCBI : standardized formats and clear navigation.



DevilInside
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26 Dec 2010, 7:10 am

I got another question, do you just care about the effects of neanderthal admixture on aspieness or on overal cognitive traits? for example, most theories of IQ divergence within human populations rely on selection theories, not admixture. Why do africans, with a proposed zero neandertal admixture, have average IQ's 2 Standard Deviations below the european mean? Either it's a rapid divergance of alleles because of selection pressures, or it's an effect of things like 70% of eurasians having a non-sapiens origin allele for brainsize regulating gene (Microcephalin). (which would include many homozygotes for this allele). However, the 0.5 to 1 SD increase seen in the ashkenazi population presumably cannot be explained by admixture because this happened VERY recently. So maybe it's a combination overal.



DevilInside
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26 Dec 2010, 7:38 am

How many PURE AFRICANS have taken your aspie quiz? you counted african-american prevalence, most all of which have about 20% european or asian (native american) admixture, and the current admixture theory suggests the introgression happened in the middle east before the lineages of europeans and asians split mostly, so i'm counting both asian and european admixture as factors that could impact results.
So, i would be very interested in the results for pure african populations



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26 Dec 2010, 10:52 am

DevilInside wrote:
yes, 23and me allows direct download of your raw SNP data, there are a few third-party applications that use this SNP data to generate their own results. you can find the reference SNP position in dbSNP or through the result of one of the third-party apps which get their SNP frequency info from that database i believe. Now i looked at your link of the neanderthal genome, could you tell me which damn files are actually relevant to the actual genome sequence? there are a shedload of differen files on there with no indication of which is which. this is why i prefer NCBI : standardized formats and clear navigation.


I cannot find any convinient way to navigate it either. My suspicion is that I will need to download the data (which is several GBs large), convert it to binary form, and write a program to get what I want. What I would want is to find a specific position relative to the human genome, and find a specific DNA-sequence.



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26 Dec 2010, 11:00 am

DevilInside wrote:
How many PURE AFRICANS have taken your aspie quiz? you counted african-american prevalence, most all of which have about 20% european or asian (native american) admixture, and the current admixture theory suggests the introgression happened in the middle east before the lineages of europeans and asians split mostly, so i'm counting both asian and european admixture as factors that could impact results.
So, i would be very interested in the results for pure african populations


There is no way to directly measure pure African prevalence with Aspie-quiz. The measure I talked about before relates to interest rates in the US population compared to proportion of US population. Since about 15% of the participants get "very likely Aspie", and the rate of Aspie in the general population is a magnitude less, being an Aspie is a predictor for doing Aspie-quiz. Therefore, if some population in the US has 1/6 of the participation rate, they also must have lower prevalence.

Reference: http://www.rdos.net/eng/Aspie-quiz.pdf (look at table 3).



DevilInside
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26 Dec 2010, 1:55 pm

I do not necessarely agree with that conclusion.. wouldn't african american be far less likely to end up on an aspie quiz because of environmental factors? please, if you are going to include these statistics to draw conclusions, refrain from conjectures which might ignore important variables? I know that one of my black autie friends is considered to be "too white culture" in his thinking and ignored by his family, so i think many would not even WANT to find out if they're different. Also, i would still like an answer on your views of lower african IQ :)



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26 Dec 2010, 5:12 pm

DevilInside wrote:
I do not necessarely agree with that conclusion.. wouldn't african american be far less likely to end up on an aspie quiz because of environmental factors?


The problem with environmental and every other type of variables, is that afroamericans are steady on the 1/6 level of participation over a time-frame of several years, and a shift in whom does the quiz from mostly autism community people to mostly neurotypicals. Also, the Native American group consistently have higher participation rates and high scores, while people of Asian (probably mostly south asian) descent have lower scores and similar participation. The results of the Native American group tends to exclude racism and discrimination as a possible cause.

DevilInside wrote:
Also, i would still like an answer on your views of lower african IQ :)


It is really easy. IQ tests measures hybrid vigor. They measure positive traits we got from Neanderthal.



DevilInside
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26 Dec 2010, 6:57 pm

IQ tests measure hybrid vigor, how do you prove that? and can't that also be partially explained by divergence in the SAPIENS genes (remember the neanderthal admixture states 1 to 4% admixture which differs per case, not necessarely sweeping alleles across the whole population). Some alleles might have been more positively selected for though, again we need the exact sequences to say for sure.



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27 Dec 2010, 1:23 am

friedmacguffins wrote:
Respectfully, we don't look at a happy person, and ask whether he was feeling pressured.

IMHO, it's pressures, which drive species to extinction.

I appreciate that my worldview may not be what you were used to.

Pressures can cause adaptations through mutations, adaptations through skills and thinking or extinction. All of them are possible outcomes :)



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27 Dec 2010, 3:43 am

DevilInside wrote:
IQ tests measure hybrid vigor, how do you prove that?


I have no idea. I'm not so interested in IQ, but I've read the elementary literature on the subject, like "the g-factor". What they claim is that the g factor is the primary factor that comes out of education-like tests. There is no reason to doubt that, but the g factor is not any of the primary factors in Aspie-quiz. It is possibly the 3:rd factor that explains about 1% of the variance, but right now I cannot prove it since I've not had any traditional IQ-test in Aspie-quiz. All I've done in a very early version was to construct my own nonverbal IQ test, and it does correlate well with the 3:rd factor in Aspie-quiz. Some questions that seems to be related to IQ does as well.

While this is speculative (I cannot prove why it is so), the factors in Aspie-quiz are related to population events. The primary factor is related to the start of the ice-ages about 1.8 million years ago, and this is the time we can trace the start of the formation of the Aspie phenotype to. The secondary factor is related to the formation of modern humans, by hybridization. The third factor is related to the actual interbreeding between modern humans and Neandethals. That is also why I think the third factor ( = g factor) is related to hybrid vigor.

DevilInside wrote:
and can't that also be partially explained by divergence in the SAPIENS genes (remember the neanderthal admixture states 1 to 4% admixture which differs per case, not necessarely sweeping alleles across the whole population). Some alleles might have been more positively selected for though, again we need the exact sequences to say for sure.


The admixture is not generally spread all over the population, rather it is concentrated to a smaller subpopulation. Only a few genes have made "selective sweeps". Most are involved in balanced selection. But this is an issue that we probably will soon get some answers on soon.