Posted by alexandra_k on September 27, 2006, at 8:34:49
In reply to Re: genetics of schizophrenia » alexandra_k, posted by SLS on September 27, 2006, at 7:19:21
> I really am not on top of the research regarding which chromosomes and which loci are currently suspect as being associated with schizophrenia.
Neither am I.
I guess what it comes down to is whether there will be certain combinations of allels that on some abstract level are necessary and sufficient for the disorder or whether environment plays a more substantial role in the way the allels express.
I mean...
I can't remember what the 4 different meanings of innate / genetic were...It comes down to stuff like...
You would think that sexual behaviour in monkeys (in terms of mating) would be genetic if anything was.
But if you raise a monkey in isolation from its peers for a time and then place it in with some peers then it never does develop normal mating behaviour.
That is an extreme example of how the environment can play a substantial role in allel expression.If the environment does indeed play a substantial role (so that more subtle features of the environment have a significant impact) then it might well be the case that we won't be able to find a certain combination of allels that are necessary and sufficient for the disorder no matter how abstractly we define the relevant combinations.
I think the trouble with twin studies is that...
There aren't very many identical twins where one (or both) are affected with schizophrenia. But that being said I'm fairly sure there are some cases where only one developed schizophrenia. Identical twins have the same genes / allels so that would mean that the genes / allels aren't sufficient to determine whether one develops schizophrenia or not. One would also expect that if one was exposed to a virus in utero that the other one would have been too...
Actually... Thanks for that :-) It shows that no matter how abstractly we define combinations of allels... Genetic inheritence isn't enough to determine whether one has schizophrenia or not. Environment must play a role.:-)
> Similar studies are available for bipolar disorder. Elliot Gershon has done much work on this. I believe he was one of the contributors on the work with the Amish community.
Thanks. I'll look that up.
A fair few theorists have argued that schizophrenia isn't a natural kind. Instead they think that there are importantly different types of schizophrenia. If that is right... Then if we divide 'schizophrenia' up into the relevent types then we might have better luck with figuring out what is going on...
I'm not sure how much schizophrenia is an either / or syndrome either. I have heard a number of cases where people were dx'd with schizophrenia and when they got better they were told they must have been misdiagnosed. That is one way to make a disorder chronic by definition.Then there are related conditions like brief psychotic episode and schizotypal personality etc etc...
I'm just learning... But I guess I've been reading a lot. I feel like it goes in one ear and out the other sometimes... Trying to retain more of it...
poster:alexandra_k
thread:689461
URL: http://www.dr-bob.org/babble/20060927/msgs/689558.html