Email from Autism Speaks about prenatal testing

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Here's one part of an email exchange I had with Autism Speaks. In short, it's more complicated than it sounds and they are aware of ethical issues, but if possible they someday hope to do it ethically. They sound a lot more reasonable than they used to be so maybe it would be possible to organize and put enough pressure on them (while being civil) to get them to support a ban on prenatal testing until abortions of babies with disabilities can be heavily discouraged, and get that in place before such a test is feasible. I hope to continue this dialogue with them.

Mr. [Browning],

That is an excellent question.

One of science's most redeeming and frustrating qualities is that it is unpredictable. We never know what we will discover or learn. There is certainly potential to find genetic markers for ASD, and these markers could be used for prenatal testing, but this screening potential is wrought with problems. Things are rarely straight forward.

Unlike Huntington's disease (and others), ASD is a multi-genetic disease. One that involves many genes within our genome. From what we can tell, or at least surmise, is that autism results from the combination of many genes, most of which we have yet to discover. Additionally, environmental factors influencing or acting on these genes certainly is playing a part as well.

So having a genetic test for ASD could suggest autism in a child within the womb, but it would be difficult to be as certain as say a test for Down Syndrome, where the genetic component is quite obvious and testable.

Additionally, prenatal tests have limits. Again lets use Down syndrome as an example. Down syndrome, when suspected, can be tested by using a common method termed the Triple Test: Amniotic fluid aspiration, Chorionic Villi biopsying and maternal serum. All of these are done in the second trimester, with the combination of all three tests being used to help discern if the fetus has Down Syndrome. Despite this, all three tests, even in combination, have error rates that make this battery less reliable than we would hope. The most definitive test is a specific ultrasound test (nuchal translucency) in the third trimester. Though highly accurate, this verification of a Down child is only discerned in the third trimester. For autism, and its complexity of phenotypes and genetic/environmental influences, I would suspect that a robust prenatal screening would be even more difficult.

Embryo biopsy and genetic screening, though very accurate if done correctly, could be a useful approach. However, this method can only be conducted in an in-vitro fertilization (IVF) lab utilizing the IVF surgical process (conception would have to be artificial). Screening could only tell you if the genes are present or missing and NOT how they are functioning. A genetic screen is only definitive if the genetic component is dominant. Meaning, that if you get/lose the gene you have the disease. Again, Down syndrome is an excellent example.

An added caveat to this is elected abortion. Science can resolve many problems, but it also can create them. Cleft pallet is a developmental state that can be detected in the third trimester of gestation. Though benign in of itself and certainly surgically correctable with minimal to no scarring, it currently ranks as the second most common reason for elected abortion in the UK. The reason being is that there is a weak association of cleft pallet and the possibility of mental retardation. Meaning that there is an observance that babies born with a clinically diagnosed form of mental retardation sometimes also have a cleft pallet. This does not mean that a cleft pallet is a sign of retardation. It only raises the risk by association. Regardless, this observance by ultrasound late in gestation is enough for some to elect for an abortion.

Ultimately, the goal of a definitive prenatal test, if achievable, would be to have gestational intervention to correct or temper any developmental abnormalities. I certainly hope we can accomplish this, but we are still years away from such an accomplishment.

Thank you for sharing the post John Browning.

Thanks for sharing, that was interesting

I don't think prenaltal testing will ever give a reliable indication of whether someone will be on the autistic spectrum and where on the spectrum they are likely to be. Environment/gene interactions are horrificly complex if not impossible to predict. Most of the mutations linked to autism are slight modifications of certain genes that pop up in a single individual or a handful of individuals at most. There would be no way to distinguish between a fetus that was going to become profoundly autistic, one that was going to be AS/HFA, one that was going to be on the Broad Autistic Phenotype (e.g a large percentage of those who have decent technical abilities) and one that was going to become NT. Realistically the best you might be able to say in a few years time is something along the lines of:

"This fetus has an unusual mutation on a gene that has been linked to autism spectrum disorders. It may cause one or more of the proteins it codes for to be more or less active. Having looked at the family history and the potential interactions this mutation may have with other genes in the fetal genome, we estimate there is an X% chance that this fetus could have an ASD. It's chances can be improved by avoiding (environmental factors). We recommend it be monitored after birth for any signs of Autism so appropriate interventions can be made"

I think most parents'll be asking for an abortion as soon as they hear the "A" word, whatever the fetuses chances of being an NT. However happy Autistic people can be, however well they can do with appropriate intervention and support, and however badly the positive traits posessed by many Autistics and those in the Broad Autistic Phenotype are needed, very few people would want to give birth to a potentially Autistic child and rear it if they had the choice. It'll be kinda like the problem with girls currently faced in many areas of India and China: needed, not wanted, selectively aborted.

A leading Genetic expert was recently quoted as saying, The Human Genome Project scores near zero as a predicter of anything.

Even comparing profound autism and HFA, there is no genetic differance, No batch could be sorted between the Autistic and the NT.

There is something else going on, and it will take long and broad study to find.

Inventor, is it possible that there's a greater difference between NTs and autistics than between HFA and LFA? Just saying.

I'd rather be alive and autistic, than an abortion statistic.

How about normal due to prenatal drugging? That, if it's possible, is what Autism Speaks actually wants.

I doubt you'd actually be able to tell who was going to be autistic and who was going to be broad autistic phenotype/ an unaffected carrier on the basis of a prenatal gene test in most cases (too many environmental factors to account for). But hey, we don't need those weirdos and introverts, do we?

We need autism. We need to maintain a certain (small) number of autistics to keep society functioning. Ideally, autistics should be like Icelandic leadersheep. (http://www.lavenderfleece.com/leadersheep.html)

@ autism speaks.

Thanks for sharing.

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The idea of "curing us" before birth kinda makes me uneasy. It's hard not to empathize for those with the worst cases of Aspergers and Autism. It can be a really rough life, and I can totally see and support a desire to be "cured". But for most of us, myself included, I take offense to the notion that we need to be "cured". Sure we're a little different, but what's wrong with that? Just cause it's labeled a disorder, doesn't mean it IS one. Remember, at one pt, Homosexuality was considered a disorder.

I dunno, maybe I lack proper perspective because my aspergers isn't as severe as it could be, but to me, it's just part of who I am.

I know what you mean. There's a certain steroid (Decadron) thought to prevent lesbianism (seriously... look it up) and although you might think "Hey I don't want my daughter to be confused or scared or discriminated against" there's just something SO creepy about messing with what WOULD ordinarily happen.

If it's not fatal, just inconvenient, then leave it alone.

I agree 100%. Very well said.

Interesting thread. Must read for all. Especially in light of the Autism Speaks deal brokered with Alex