Aspies For Freedom

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The search for susceptibility genes
Although the strong genetic predisposition to autism is no longer in
doubt, identifying susceptibility loci is not straightforward (Box 2). In
the absence of specific drug effects and detailed knowledge of the underlying pathophysiology, there are no very strong pointers to functional candidate genes. Of course, the well-established association
with various medical disorders has been pursued but, for instance, no
linkage has been found with the fragile X mental retardation 1 gene
(FMR1) (Ref. 5). The finding of elevated platelet serotonin levels in
perhaps a quarter of cases has prompted association studies of the serotonin transporter and various serotonin receptor genes with, so far, no clear pattern of findings 6–8 . Indeed, as yet, there are no particularly
strong leads from any of the case-control or family-based candidate-gene
association studies, although the likelihood of genetic hetero-geneity
has not been systematically assessed.
With regard to positional candidates and regions, most attention has
recently focused on the proximal portion of the long arm of chromosome
15 (Ref. 1): a region in which chromosomal duplications and
other rearrangements are sometimes associated with an autistic phenotype with apparent imprinting effects. The presence of a cluster of
g-amino butyric acid (GABA A ) receptor genes in this area has partially
fuelled this interest, but association studies in this region have so far
yielded inconsistent results .
A complication for molecular genetic approaches is that the substantial
difference between the concordance rates for autism in MZ and
DZ twin pairs suggests that autism does not represent a single-gene
disorder. The twin and family findings indicate a multi-locus disorder,
with one model suggesting that 2–10 interacting genes are likely to
underlie susceptibility.
Although some of the data support a model of
epistatic interactions between a small number of loci, there is not really
sufficient evidence to strongly support any particular hypothesized
complex mode of inheritance. As autism is associated with several distinct
medical disorders, genetic heterogeneity among idiopathic cases
also seems likely, although phenotypic markers of potential heterogenity
are limited.


Pre-natal and pre-symptomatic testing
At present, it is unclear whether the current interest in pre-natal testing
for monogenic disorders will eventually apply also to autism and related
complex disorders. Obviously, the potential to test for the presence
of a high-risk genotype could significantly influence genetic
counselling to affected families. Nevertheless, the complex gene interactions that are suspected to underlie autism suggest that testing is
unlikely to be a straightforward issue. In particular, the apparent non-deterministic nature of the genetic influences – as evidenced by the
substantial degree of phenotypic variability – means that knowledge
that an individual carries one or more of the susceptibility genes for
autism might not strongly predict a particular outcome. Moreover, it is
possible that susceptibility loci also contribute to traits that are beneficial
– for instance, elevated IQ or single-mindedness.
There might be genetic variants of autism for which testing could be
viewed as potentially more useful. That situation might arise if a
particular genetic predisposition was strongly associated with a severely
disabling disorder, a particular disease course, or the development
of complications such as epilepsy. Genetic knowledge might then
predict the need for particular environmental, behavioural or medical
interventions.

link
Welcome, I know a few apsies called Alex, but I know many more called Matthew, about 12 of them.

Guest

Nemadaelius asks:

has anyone else noticed that a significant fraction of Aspies seemd to be named, or alternately related to someone who is named, Alex? My name is Alex, and I recall having seen perhaps two or three mentions of Aspies named Alex on various sites, such that they are unlikely to be referring to the same person. MY best freind is named Alex, and while he doesnt have AS, his little brother does. Its probably no more than a minor coincidence.


1.  Asperger's Syndrome has only been recognized as a distinct condition in the USA since (about) 1993.

2. The popularity of certain names fluctuates temporally and:

3. demographically according to fashion and:

4. Socio-economically according to fashion

Combinations of 1. , 2. , 3.,  and 4. could result in a higher probability density of finding the name "Alex" amongst young persons presenting AS in a particluar part of American society at a particular time.

Does this sound sensible?  :idea:

Best Wishes,

Stella Maru.

Guest

hmmm: I wonder why I appear as "guest"...  its me Stella.

Perhaps I forgot to log in!  :idea:

Stella.

Guest

http://www.google.com/search?hl=en&lr=&s...tnG=Search

i think you can find something there
(had to find out what SNP stood for)
whatever is discovered among all the bits and pieces of junk DNA, we will be here all the same.

Stella Maru
Nemidaelius, I can  see how questions of nosology and taxonomy may be very interesting in their own right.

It becomes a problem when applications are generated  in response to the "discovery" of these classifications.

It is not unknown for parents with money to pay to have their child "upgraded" from HFA to AS, by seeking a "second opinion" from another medic. But this makes no difference to the child.

Wealthy parents are able to pay Social Services to go away, which means poorer families are disproportionately targeted by predatory Social Workers. The Social Workers are attracted to the family by the chracteristic aroma emanating from the diagnosis, much as vultures are attracted by the odour of cadaverine.   :lol:

Stella Maru
People want to cure Huntington's as it is fatal, very much unlike ASD's.

You said "If and when the causes of AS are determined, we will have plenty of time to prepare and to do our own research before any applications are possible."

How will we have plenty of time? Why wont applications be used straight away? I wonder often about the research that must be going on in Japan, they have fairly high rates of autism there, and are extremely ahead of other countries in terms of embryology study, what must they be working on?
I have tried to search, and translate, but its very difficult, does anyone have any information on the prospect of a cause or cure from Japan?
I wonder if we could find a timeline for discovering causes and then action taken, such as for Down's?
If we could find such information and chart it, we will be more prepared for possible outcomes for autism.
I can tell you how much I've had (in fact, I've already done so, but pressed the wrong key and it all disappeared!) which is namely what I was taught by a school-teaching ignoramous (who thought a rabbit had {and needed} better binocular vision than a fox as it's eyes are, relatively speaking, wider apart!). I understood the absurdity of his "understanding" in my early teens, but he had a successful career and I have not!

OK, I'm waffling; but when I saw the title to this tread, I thought (to use the US vernacular) "yeh...right!".

Guest

When I was small I went to a "School for the Educationally Subnormal." or ESN School as it was called.

Most of the teaching was like this:

"Always look at the person you're speaking to, take a deep breath before you begin, always remember to roll your Rs, and don't fidget while you talk."

We also learned a lot of things by chanting. Multiplication tables for example: two twos are four, two threes are six, two fours are eight..."
And "The square of the hypotoneuse is equal to the sum of the squares of the other two sides."

We also learned how not to make a slurping noise while drinking soup and how to lay a table and how to sew on a button.

Stella Moo

Guest

These are our lives and we have to live them all the same.
Gosh Stella, those teachers of yours really saved you from a lot of grief didn't they? Fidgetting while you talk is so life threatening!  Tongue

But seriously, I've had a rethink; these guys do seem to know what they are doing, even if they are coming from a dubious base understanding.

Amy Wrote:
A complication for molecular genetic approaches is that the substantial
difference between the concordance rates for autism in MZ and
DZ twin pairs suggests that autism does not represent a single-gene
disorder. The twin and family findings indicate a multi-locus disorder,
with one model suggesting that 2–10 interacting genes are likely to
underlie susceptibility.


Well we could have told them that (in fact it's probably at least double that number) but shouldn't they have realised that it also depends on the presence of balancing genes (autism is also the absence of traits, so genes for "non-autism" may well mitigate or modify the activity of genes for autism). In fact, it's highly likely that what the medics term autism is really a hybridisation problem, and that the autism genes themselves are not the issue; it becomes a problem only when they are combined with other genes that are incompatible, in which case it would be equally valid to blame, or seek to eliminate those other genes. Will they ever get it do you think?

Quote:
As autism is associated with several distinct
medical disorders, genetic heterogeneity among idiopathic cases
also seems likely, although phenotypic markers of potential heterogenity
are limited.

and also things that cannot be properly called disorders (except by the establishment control freaks; but why should they have the sole right to decide what's acceptable?) like the attributes which gave us Newton et al!

Quote:
Moreover, it is
possible that susceptibility loci also contribute to traits that are beneficial
– for instance, elevated IQ or single-mindedness.


Well gosh, there it is (and single-mindedness is something they consider beneficial? How enlightened of them!) so why don't they take note of their own argument?

I'm pretty sure I had this when younger (many others here have reported similar dificulties) but it went away when I conditioned myself to accept that if the choice is difficult, the outcome is inconsequential. It's then just a matter of training oneself to make a spur of the moment decision (and, and this is important, not to allow oneself to reconsider). It may sound like Zen (and there's nowt wrong with Zen for that matter, other than it's sense tends to get lost in the translation) but essentially, you just keep telling yourself that next time you are presented with a fairly balanced choice, that you will make an immediate decision, and stick to it. Like every thing it takes practise and will power, but every time you succeed, it gets easier (and every time you fail, you take a step back). Keep working on it, and keep asking if there's any useful purpose to agonising over whether you should have the orange or rasberry flavoured drink (for example) and it's all conspire to take away the anxiety that you may make the wrong choice.

It takes time and perserverence, but someday you'll realise it's become automatic, and then you'll be able to apply the same kind of "self hypnosis" on other such issues.

Can't help your dog though.
OK, so it's more complex, but the basic issue is the same; you can condition yourself to make a premptive decision, and stick to it (and I know people who have tried and succeeded in this technique). I'm not suggesting for a moment that it's easy, nor that it can be mastered over-night, you need to be in for the long term; but what have you got to lose? Given the circumstances, you're hardly going to be "wasting time" by trying to acquire this skill!
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