Hard Light Productions Forums

Off-Topic Discussion => General Discussion => Topic started by: Kosh on December 21, 2008, 08:32:54 am

Title: Child with no breast cancer causing gene
Post by: Kosh on December 21, 2008, 08:32:54 am
 Awesome stuff (http://science.slashdot.org/science/08/12/19/231223.shtml)


Quote
manoftin writes to tell us that next week a baby will be born without the gene for breast cancer, according to the BBC. "But he said that, in this case, not carrying the BRCA1 gene would not guarantee any daughter born to the couple would be unaffected by breast cancer because there are other genetic and environmental causes. Dr Alan Thornhill, scientific director of the London Bridge Fertility, Gynaecology and Genetics Centre, said: 'While the technology and approach used in this case is fairly routine, it is the first time in the UK that a family has successfully eliminated a mutant breast cancer gene for their child. It is a victory for both the parents and the HFEA that licensed this treatment.'" 


This is the first step to eliminating all kinds of terrible genetic conditions.
Title: Re: Child with no breast cancer causing gene
Post by: Mars on December 21, 2008, 10:21:00 am
Awsome stuff.

Is there any chance of eliminating the wrong gene, however? Causing a mutation that could be worse than the original.
Title: Re: Child with no breast cancer causing gene
Post by: Black Wolf on December 21, 2008, 10:38:49 am
Awesome stuff (http://science.slashdot.org/science/08/12/19/231223.shtml)


Quote
manoftin writes to tell us that next week a baby will be born without the gene for breast cancer, according to the BBC. "But he said that, in this case, not carrying the BRCA1 gene would not guarantee any daughter born to the couple would be unaffected by breast cancer because there are other genetic and environmental causes. Dr Alan Thornhill, scientific director of the London Bridge Fertility, Gynaecology and Genetics Centre, said: 'While the technology and approach used in this case is fairly routine, it is the first time in the UK that a family has successfully eliminated a mutant breast cancer gene for their child. It is a victory for both the parents and the HFEA that licensed this treatment.'" 


This is the first step to eliminating all kinds of terrible genetic conditions.

And Gattaca! Woo!
Title: Re: Child with no breast cancer causing gene
Post by: castor on December 21, 2008, 01:25:55 pm
Awsome stuff.

Is there any chance of eliminating the wrong gene, however? Causing a mutation that could be worse than the original.
I think this is more like abortion due to medical reasons. Just without (or before) the fetus.
Title: Re: Child with no breast cancer causing gene
Post by: tinfoil on December 21, 2008, 03:33:03 pm
Awsome stuff.

Is there any chance of eliminating the wrong gene, however? Causing a mutation that could be worse than the original.

you mean like the the movie I Am Legend?
Title: Re: Child with no breast cancer causing gene
Post by: Mars on December 21, 2008, 03:39:10 pm
Never seen it >_>
Title: Re: Child with no breast cancer causing gene
Post by: tinfoil on December 21, 2008, 03:40:58 pm
well essentially a cure for cancer goes really really bad. the analogy doesn't work if you haven't seen it though.
Title: Re: Child with no breast cancer causing gene
Post by: Kosh on December 21, 2008, 08:16:12 pm
It's not like that, they didn't alter anything, they just screened the embryo to make sure it didn't have that particular gene.
Title: Re: Child with no breast cancer causing gene
Post by: MP-Ryan on December 22, 2008, 05:36:18 am
See, this is why I have a genetics degree.  Well, primarily it nicely adds to my resume, but a good secondary bonus is the ability to explain this crap to people =)

Here's what this couple did:
-Mom tested positive for BRCA1, a genetic predisposition to breast cancer.
-Doctors remove several of Mom's eggs and a great deal of Dad's sperm.
-Eggs are individually separated onto growth medium, and fertilized.
-Successful fertilizations are kept and the embryo is allowed to grow to the 8-cell stage; unsuccessful fertilizations are discarded.
-At the 8-cell stage, a single cell is removed from each embryo.
-The cell is digested in a series of chemicals, and a polymerase chain reaction (PCR) is run to determine the presence or absence of the BRCA1 gene in each embryo.
-Embryos that tested positive for the BRCA1 gene were destroyed.
-Some (usually 4-6) of the embryos testing negative for BRCA1 are implanted into Mom's uterus while she's given a hefty dose of fertility drugs and hormones.  The remainder are frozen in storage.
-Hopefully, at least one of the embryos implants into the uterine lining, and Mom is now officially pregnant.
-Providing all goes well, Mom gives birth to [a] healthy child[ren] 40 weeks later.

This is IVF (in-vitro fertilization) with genetic screening done to weed out the chance of a particular gene.  It's nothing revolutionary - the technology to do this has existed for nearly two decades (possibly longer, actually).  It's very time consuming and it involves the destruction of a lot of embryos.

This is the short cut to getting pregnant and aborting each pregnancy when it tests positive for the cancer gene.  Instead, you eliminate the chance of a fertilized embryo carrying the gene even implanting into the uterine lining.

It has nothing to do with any the the absolute garbage that movies make the science of genetics out to be.

And this is actually a step BACKWARD in eliminating problematic genetic conditions - rather than seeking an actual solution or gene therapy for people born with the condition, people will merely seek to have designer babies instead.  I don't have much problem with that so long as PGD is restricted to life-threatening conditions, but the potential for abuse of this science is enormous.
Title: Re: Child with no breast cancer causing gene
Post by: Stormkeeper on December 22, 2008, 08:30:30 am
How soon till the first Co-ordinator (http://en.wikipedia.org/wiki/Cosmic_Era_human_enhancements#Coordinators)?

I'm sorry, I couldn't resist, especially not when I saw 'designer babies' in Ryan's post ...
Title: Re: Child with no breast cancer causing gene
Post by: karajorma on December 22, 2008, 09:01:38 am
the potential for abuse of this science is enormous.

Not until the steps you just mentioned get a lot easier though. Right now it's really not worth it just for designer babies. Especially when you consider the discomfort involved with egg donation and the success rate of IVF.
Title: Re: Child with no breast cancer causing gene
Post by: chief1983 on December 22, 2008, 11:10:17 am
But even now, with the increased risk that we frak something up, you basically make it ok to terminate the mistakes.  Instead of one aborted natural fetus, you have many aborted clinical fetuses.  If people had a problem with abortion before, can you imagine the flames this is going to cause?  I might be pro-choice, but that doesn't extend so far as to tell people it's ok to try to fine tune life and then kill it when they screw it up.  And I'm not so worried about designer babies as I am about making our gene pool even more stagnant.  We're choosing to halt evolution.  I could see it getting to the point that the equivalent of a jury needs to exist to determine what kind of genetic manipulation should and should not be allowed, so that we have as minimal an effect on our genetic diversity as we possibly can.  Who's to say that many things that might be undesirable traits today won't be the key to the survival of the species tomorrow?  If this kind of modification is to be allowed, it should only be to prevent the most serious of illnesses and afflictions, the rest should be left up to nature.
Title: Re: Child with no breast cancer causing gene
Post by: Mars on December 22, 2008, 11:13:10 am
Didn't we already choose to halt evolution . . . really
Title: Re: Child with no breast cancer causing gene
Post by: chief1983 on December 22, 2008, 11:18:09 am
Not so terribly much, we still have maintained a certain level of diversity among the population.  But if everyone can make themselves even more alike, that gets hurt even more, and an environment change on a global scale could wipe us all out.
Title: Re: Child with no breast cancer causing gene
Post by: Kosh on December 22, 2008, 12:08:23 pm
Quote
And this is actually a step BACKWARD in eliminating problematic genetic conditions - rather than seeking an actual solution or gene therapy for people born with the condition, people will merely seek to have designer babies instead.  I don't have much problem with that so long as PGD is restricted to life-threatening conditions,

Not a clean win, granted. However, what about conditions like down syndrome and muscular dystrophy? They aren't life threatening but they can make your life a living nightmare.

Quote
but the potential for abuse of this science is enormou

Which is what regulation is for.

Title: Re: Child with no breast cancer causing gene
Post by: Mongoose on December 22, 2008, 06:55:58 pm
Not gonna lie, this sounds pretty damn horrific.  I'm not intent on opening any old cans of worms, though.  Ah, humanity...your endless potential for destroying what makes you you in increasingly inventive ways never ceases to amaze me.
Title: Re: Child with no breast cancer causing gene
Post by: Martinus on December 23, 2008, 01:42:22 am
I probably sound quite nasty in saying this: The lovely thing about it is that the people who get hung up on calling a small number of cells sacrosanct life won't matter. They'll be the ones with the higher mortality rate and less chance of breeding genetically robust offspring.

The level of fear-mongering and pessimistic conjecture associated with work like this is almost humorous.

We are still evolving when our hand guides the path. Who stated that evolution had to happen completely by chance?
Title: Re: Child with no breast cancer causing gene
Post by: tinfoil on December 23, 2008, 02:06:27 am
I'm so, so glad Trashman isn't here to wreak his havoc on this thread.
Title: Re: Child with no breast cancer causing gene
Post by: karajorma on December 23, 2008, 02:24:59 am
But even now, with the increased risk that we frak something up, you basically make it ok to terminate the mistakes.

How? You've lost me there. I fail to see how an time-expensive and costly procedure which is only likely to be used by people who had decided to not have children in the first place in order to prevent them from having horrible inherited conditions is going to screw anything up.
Title: Re: Child with no breast cancer causing gene
Post by: Mongoose on December 23, 2008, 04:05:11 am
I probably sound quite nasty in saying this: The lovely thing about it is that the people who get hung up on calling a small number of cells sacrosanct life won't matter. They'll be the ones with the higher mortality rate and less chance of breeding genetically robust offspring.
Yes, you do sound quite nasty, but no matter...those of us who hold such beliefs tend to wind up having more kids than those who don't, so I suspect it all balances out in the end. :p

On a more serious note, I don't see it as fear-mongering so much as pointing out a rather glaring (and rather disturbing, at least to me) case of bad ethics going on.  I should think that the phrase "designer babies" would give anyone pause who stops and gives it serious thought.  By selectively weeding out certain traits, are we saying that those who exhibit such traits (for a nice and prominent example, let's say Down's Syndrome) are somehow "unworthy" in some sense, belonging to a prior and inferior class of humanity?  And this sort of technology could easily go so far as to toss around embryos for the sake of getting a baby with the "right" eye color...even without invoking certain Internet laws, that's one of the most callous forms of superficial behavior I can think of. 

And going in an entirely different direction, if we're going to be sticking our hands in a process that's literally taken billions of years to get our genome to where it is today, we'd better be damn sure we know what we're doing beforehand.  What sounds great in theory and initial practice could very well turn out to be disastrous down the road.  It's only been fifty years or so since we discovered just what the molecule is that makes us all tick, and a mere five since we established a rough blueprint of everything that that molecule does.  Maybe before we go bounding off into some magical Brave New World, we should sit down and talk about exactly what that world implies.
Title: Re: Child with no breast cancer causing gene
Post by: karajorma on December 23, 2008, 04:29:55 am
And this sort of technology could easily go so far as to toss around embryos for the sake of getting a baby with the "right" eye color..

That's kinda the point I've been trying to refute for the whole length of this thread. It isn't easy. As MP_Ryan said the technology to do this has existed for a long time. If it was easy why would it have been sitting on the shelf for so long?

Quote
are we saying that those who exhibit such traits (for a nice and prominent example, let's say Down's Syndrome) are somehow "unworthy" in some sense, belonging to a prior and inferior class of humanity?

If you can find me one person with Down's Syndrome who hopes their child has Down's Syndrome too I might believe that we live in a world where people with it don't already consider themselves in some sense "unworthy". Down's is actually a bad choice as if I understand it correctly anyway, as it's caused by a failure of the chromosome to replicate properly and not due to any actual problem with the gene itself.

But let's suppose we are dealing with a proper hereditary condition. How is not having children at all because you are worried about passing it on an improvement? If you really feel that this could make someone feel unworthy then the fact that people willingly give up their chance to be parents just to avoid having children with the same condition is surely going to make them feel unworthy too?

I don't see why there has to be a dichotomy between saying that people with crippling genetic conditions are fully human and in no sense "unworthy" and saying that I wish we'd never have another child born with Cystic fibrosis or Tay-Sachs.
Title: Re: Child with no breast cancer causing gene
Post by: chief1983 on December 23, 2008, 10:00:10 am
I'm not even saying it shouldn't but done, but saying it's not something to be concerned about seems kind of ignorant too.  You can throw out good examples of truly crippling genetic problems all day long, I'm not denying that, but what several of us already said is where do you draw the line?
Title: Re: Child with no breast cancer causing gene
Post by: karajorma on December 23, 2008, 10:13:03 am
Fair enough but it's not like questions of where you draw the line on medical issues are anything new or something to get into a tizzy about.

As I've pointed out this isn't going to result in designer babies any time soon since it's bloody expensive to do so. There is plenty of time to get the necessary regulation in place. No need for everyone to run around screaming about how we're messing with nature.
Title: Re: Child with no breast cancer causing gene
Post by: Mars on December 23, 2008, 10:16:02 am
Meh . . . stupid neo-cons will have a field day with it, to be sure.
Title: Re: Child with no breast cancer causing gene
Post by: peterv on December 23, 2008, 10:31:49 am

If you can find me one person with Down's Syndrome who hopes their child has Down's Syndrome too I might believe that we live in a world where people with it don't already consider themselves in some sense "unworthy".


Usually, one feels "unworthy" because of the others behavior.
Believe me, i've worked whith people whith Down's Syndrome an i know at least two off them ho feel anything but "unworthy". Off course they' re both very well protected by their families.
Title: Re: Child with no breast cancer causing gene
Post by: General Battuta on December 23, 2008, 11:26:48 am
Didn't we already choose to halt evolution . . . really

Just wanted to jump in and point out that the human race has actually been evolving faster in the past few centuries than ever before.

Evolution is defined as the rate of allele flow, which has been very high.
Title: Re: Child with no breast cancer causing gene
Post by: MP-Ryan on December 23, 2008, 12:57:42 pm
And this sort of technology could easily go so far as to toss around embryos for the sake of getting a baby with the "right" eye color..

That's kinda the point I've been trying to refute for the whole length of this thread. It isn't easy. As MP_Ryan said the technology to do this has existed for a long time. If it was easy why would it have been sitting on the shelf for so long?

Quote
are we saying that those who exhibit such traits (for a nice and prominent example, let's say Down's Syndrome) are somehow "unworthy" in some sense, belonging to a prior and inferior class of humanity?

If you can find me one person with Down's Syndrome who hopes their child has Down's Syndrome too I might believe that we live in a world where people with it don't already consider themselves in some sense "unworthy". Down's is actually a bad choice as if I understand it correctly anyway, as it's caused by a failure of the chromosome to replicate properly and not due to any actual problem with the gene itself.

But let's suppose we are dealing with a proper hereditary condition. How is not having children at all because you are worried about passing it on an improvement? If you really feel that this could make someone feel unworthy then the fact that people willingly give up their chance to be parents just to avoid having children with the same condition is surely going to make them feel unworthy too?

I don't see why there has to be a dichotomy between saying that people with crippling genetic conditions are fully human and in no sense "unworthy" and saying that I wish we'd never have another child born with Cystic fibrosis or Tay-Sachs.

This is a sticky issue and you've raised a lot of good points that the field of genetics itself has to contend with too.

On the one hand, we have conditions like Tay-Sachs, CF, SCID, MS, MD, etc which are crippling single-gene diseases that PGD can eliminate entirely (at enormous expense) provided the parents are screened for the disease well in advance.  I would be right there in the crowd cheering if we could ensure that a child afflicted with one of these diseases is never born with a pre-imposed early death sentence again.

That said...

I have a degree in this stuff and have been wrestling with the ethics in the field since my first year, and even I am not sure if we are meddling in areas we shouldn't be.  PGD opens an enormous can of worms.  For example, the destroyed embryos aside, we have the enormous expense of IVF with its associated chances of success, while there are large numbers of unwanted kids the world over.  Should we be genetically-screening potential births for parents who could adopt?  The second question is do we have the right to tell people to adopt when we have the technology to allow them to have healthy children?  That's just one of hundreds of ethical dilemmas regarding PGD.

Beyond that, we have the issue of regulation.  While kara has mentioned we have plenty of time for regulation of this area, we don't.  In fact, global regulations on this science aren't even in the works.  It is up to individual countries.  So, while developed nations will probably choose to heavily regulate what is and isn't allowed, there is always going to be someplace in this world where unethical bastards can get away with genetic modification of embryos for the people willing to pay for it.  I should mention that we have not yet identified the genetic basis of things like eye colour, hair colour, skin tone, etc - so while cosmetic changes aren't yet possible, if someone wanted to and had the money they could choose, today, whether they wanted a boy or a girl and make that happen.  That may seem like not such a big deal, but consider this:  Males are born at a slightly higher frequency than girls already (51%ish to 49%ish, depending on your statistician) because of the naturally higher mortality rate in young men - this results in roughly 51-49 split of girls to boys when people reach sexual maturity.  Many cultures prefer boys to girls.  Even a slight imbalance in that gender ratio has enormous implications for a country's demographics.  We can already see this effect in China.  While their population is still growing and their economy is still expanding, China is going to see a major demographic shift in the next century... which is part of the reason they are already beginning to relax the one-child policy in certain areas of the country.

The problem with the attitude of "we still have time" is that we don't.  People who have money can make this happen today, and the cost of these treatments decreases significantly every year.  Indeed, as the frequency of use increases the overall cost decreases too.  While IVF was an option for the rich or the heavily subsidized as little as 5 years ago, today any couple in the middle-class income bracket can afford it (or at least can pay for it without being forced to declare bankruptcy).

So, while I'm heavily in favour of advances in this field, this particular area requires a great deal of caution and heavy global regulation on its use.  And that just isn't happening fast enough.

As for the rate of human evolution...

As a species, with a global society we have effectively ended divergent evolution - speciation from Homo sapiens into multiple new species will not occur.  That said, with the rapid mixing of genes from different allelic populations, as someone else said we have actually sped up directional evolution - gene flow is occurring at a rate we've never seen before, and it has interesting implications for us as a species down the road.  So human biological evolution has actually sped up as a result of globalization rather than slowed down or stopped.  Human behavioural evolution, on the other hand, has slowed down dramatically and behaviour can have much larger impacts than biology in the short term.
Title: Re: Child with no breast cancer causing gene
Post by: karajorma on December 23, 2008, 01:27:46 pm
I've got to disagree with you there. While some small scale designer baby births could happen, we do have time before any large scale usage of the tech could happen. Certainly before any kind of effect on evolution could be felt.


Plus it is almost certain that the same forces of stupidity who managed to convince the middle-classes to eat organic food will be able to convince them to have organic babies too. :p
Title: Re: Child with no breast cancer causing gene
Post by: chief1983 on December 23, 2008, 01:59:37 pm
Plus it is almost certain that the same forces of stupidity who managed to convince the middle-classes to eat organic food will be able to convince them to have organic babies too. :p

Yay for stupid people in large groups then.
Title: Re: Child with no breast cancer causing gene
Post by: MP-Ryan on December 23, 2008, 02:31:51 pm
I've got to disagree with you there. While some small scale designer baby births could happen, we do have time before any large scale usage of the tech could happen. Certainly before any kind of effect on evolution could be felt.

The problem is that if a demand is created, it's very difficult to curb the supply.  It would have been better to have regulations in place 5 years ago or at least have them in the works now.  But we don't.  Right now it's up to medical practitioners to regulate themselves... and that doesn't always work out well.

Quote
Plus it is almost certain that the same forces of stupidity who managed to convince the middle-classes to eat organic food will be able to convince them to have organic babies too. :p

It's not often I say this, but yay for the religious and conspiracy-inclined zealots.
Title: Re: Child with no breast cancer causing gene
Post by: Mongoose on December 23, 2008, 03:27:59 pm
Plus it is almost certain that the same forces of stupidity who managed to convince the middle-classes to eat organic food will be able to convince them to have organic babies too. :p
If wanting to do things via the happy dance is stupid, then color me an idiot. :D

Quote
If you can find me one person with Down's Syndrome who hopes their child has Down's Syndrome too I might believe that we live in a world where people with it don't already consider themselves in some sense "unworthy". Down's is actually a bad choice as if I understand it correctly anyway, as it's caused by a failure of the chromosome to replicate properly and not due to any actual problem with the gene itself.
I certainly wasn't implying that anyone would willingly wish that condition on someone else, particularly someone who already  has it.  I personally feel that developmental disorders like Down's Syndrome are particularly cruel, since they lock the full potential of a human being behind an ironclad facade that they simply can't break through.  That isn't to say that people with such conditions can't accomplish amazing things, but there's always that lingering sense of "what-if" that can never be resolved. And thanks for the check on the genetic side of it; I've forgotten some of the finer details of high school biology.

Quote
But let's suppose we are dealing with a proper hereditary condition. How is not having children at all because you are worried about passing it on an improvement? If you really feel that this could make someone feel unworthy then the fact that people willingly give up their chance to be parents just to avoid having children with the same condition is surely going to make them feel unworthy too?
I honestly don't see it as an improvement at all, which is one of the reasons why I look on this procedure with such skepticism.  Regardless of how you personally feel about the status of an embryo, the fact is that you're basically flipping through them to find the ones with that desirable trait and tossing the rest aside.  I don't see that as being any different from aborting a normally-conceived embryo that one finds out has a developmental disorder, or from simply not having kids at all out of fear of encountering that sort of condition.  In every case, the parents are essentially stating that they would not accept a child with such a disorder, that the only child they'd want to raise would be one who is "perfect."  I'd say that that sort of attitude has to be just as distasteful to someone with such a condition, no matter how it's generated.

Quote
I don't see why there has to be a dichotomy between saying that people with crippling genetic conditions are fully human and in no sense "unworthy" and saying that I wish we'd never have another child born with Cystic fibrosis or Tay-Sachs.
I see no dichotomy either, and I really wish with all my heart that such conditions never had to exist in the first place.  I would just like to see that end result achieved without using potentially ethically- or socially-questionable methods.  Though it's most likely next to biologically impossible, I'd love to see a way for people who already have such conditions to receive some sort of genetic treatment that would help to alleviate their effects, so that anyone could have a shot at a full life, regardless of their condition when they were conceived.  Wishful and somewhat naive, perhaps, but I've been accused of worse.

I'm not going to lie to anyone here; I'm personally against abortion in just about every circumstance, and I view the destruction of embryos that naturally results from in-vitro fertilization or this specific procedure in light of that standpoint.  I don't expect anyone at all here to agree me; we've all seen and had that argument far more times than I think any of us wants to recall.  But even moving beyond the discussion over exactly what is being sacrificed, the concept of people spending any amount of time or money on such a procedure is one that doesn't sit right with me.  As Ryan mentioned, there are millions perfectly healthy children around the world in sore need of adoption.  Committing significant scientific and financial resources in the quest to create some sort of idealized "perfect baby," while simultaneously ignoring the myriads of children who have been already born, seems like it would be significantly objectionable from a societal standpoint to me.
Title: Re: Child with no breast cancer causing gene
Post by: karajorma on December 23, 2008, 03:49:55 pm
Given that you complained about changing the course of evolution surely you're not suggesting that responsible parents who only want to have their own children but can't due to a genetic condition give up that choice in favour of raising the children of those who weren't responsible enough to bring a child into the world they could care for?

Cause unless you're one of those 100% nurture, 0% nature types you've got to see which direction that's going to drive evolution. :p


I'll make a serious post later though. :)
Title: Re: Child with no breast cancer causing gene
Post by: Mongoose on December 23, 2008, 04:29:00 pm
Given that you complained about changing the course of evolution surely you're not suggesting that responsible parents who only want to have their own children but can't due to a genetic condition give up that choice in favour of raising the children of those who weren't responsible enough to bring a child into the world they could care for?

Cause unless you're one of those 100% nurture, 0% nature types you've got to see which direction that's going to drive evolution. :p
I was thinking more along the lines of "mistakenly insert a few alleles that wind up killing significant portions of the human race a century down the line due to decreased bacterial resistance" types of evolutionary cock-ups, not preserving a few genes which may or may not cause slightly decreased intelligence.  And basic human compassion is a wonderful thing too. :p
Title: Re: Child with no breast cancer causing gene
Post by: karajorma on December 23, 2008, 05:58:18 pm
How on earth are you expecting the insertion of extra genes to happen from this?
Title: Re: Child with no breast cancer causing gene
Post by: MP-Ryan on December 23, 2008, 06:30:39 pm
How on earth are you expecting the insertion of extra genes to happen from this?

Actually... it can happen.  Naturally, I mean.  Not through addition of extra DNA.

PGD is only looking at one gene on a single chromosome.  So, fine, you've found a naturally-conceived embryo that lacks the BRCA1 gene in this instance.  Fantastic.  Of course, that embryo could have other errors of recombination during mitosis/meiosis of the gametes, during fertilization, or during cellular mitosis between the 1 and 8 cell stages that introduce translocations, transversions, inversions, deletions, point mutations, SNPs, etc.  And before we talk about how irrelevant that can be, a single SNP can make a major difference in disease susceptibility (SNP profiles are currently the next stage in human genomics following the human genome project because of their importance).

It's fairly irrelevant to humanity as a whole on this scale, but it can be a significant risk factor because while you may eliminate a target allele, you can be adding other whole regions of DNA that are just as or more detrimental to the embryo as it grows.  Just because there's a very tiny risk doesn't negate the benefits of PGD in this instance of course, but I'm fairly sure things like this aren't getting discussed in the doctor's office prior to the decision to undergo IVF.

It's the little nuances like this that are the main reasons why it is so important to have a serious scientific discussion about regulation at the international level before the technology goes to a level where we're looking at potential for damage to populations rather than individual reproduction.

I'd also like to take issue with this:

Quote
responsible parents who only want to have their own children but can't due to a genetic condition give up that choice in favour of raising the children of those who weren't responsible enough to bring a child into the world they could care for?

Most adoptions and orphaned children have nothing to do with the fact that their parents weren't/aren't responsible.  You're painting with a really broad brush.

---

And more generally, let's briefly mention Down's Syndrome.  Down's = trisomy (three copies) of chromosome 21.  Normally you're supposed to have two.  It's one of the only trisomy's that's actually viable.  It is an error of meiosis during gamete formation, typically in the mother, and is irrelevant for the purposes of a discussion about single-gene PGD (like this one).  While PGD can identify Down's, it is not hereditary and is primarily a risk factor of mother's age.  So, not need to bring it up in further discussion for this topic =)
Title: Re: Child with no breast cancer causing gene
Post by: General Battuta on December 23, 2008, 07:52:50 pm
How on earth are you expecting the insertion of extra genes to happen from this?

Technically, he said 'alleles', which are variants of existing genes.

But I'm not taking any sides with this statement!
Title: Re: Child with no breast cancer causing gene
Post by: Mongoose on December 23, 2008, 09:29:49 pm
I don't even know that "allele" was the exact concept I was going for, but it wound up working out reasonably well. :p What I was trying to convey is that excising a certain segment of nucleotides from a particular chromosome may create a new sequence with unforeseen effects, or that attempting to deactivate the expression of a particular gene may negate some effect it was creating in concert with other genes.  We have a general idea of what the segments of our genetic code are supposed to be doing, but we have far less knowledge of how the proteins they're used to create assemble themselves, or how they interact with other sequences, or just what all of that "garbage code" is or isn't doing.  The study of our genetic makeup is something akin to someone who's never seen a computer trying to reverse-engineer one.  Right now, we've just finished identifying the general role that each piece of the hardware is fulfilling; we've barely started cracking open each chip to find out how its circuitry is arranged.
Title: Re: Child with no breast cancer causing gene
Post by: General Battuta on December 23, 2008, 10:12:17 pm
What about this?

You have a catalogue of existing alleles of one gene. You know that some alleles cause disease and others don't. Because you have many examples of people with these various alleles, you know the consequences of having them.

You select a baby that has the particular (non-disease-causing) allele you're looking for.

No introduction or excision of base pairs. No danger of an epiphenomenal failure cascade.
Title: Re: Child with no breast cancer causing gene
Post by: MP-Ryan on December 23, 2008, 11:08:08 pm
What about this?

You have a catalogue of existing alleles of one gene. You know that some alleles cause disease and others don't. Because you have many examples of people with these various alleles, you know the consequences of having them.

You select a baby that has the particular (non-disease-causing) allele you're looking for.

No introduction or excision of base pairs. No danger of an epiphenomenal failure cascade.

That would be perfect, if it weren't for the recombination going on in the roughly 2.994 billion other base pairs of the genetic code during meiosis.  The replacement allele that you're getting isn't the problem - it's everything else along with it.
Title: Re: Child with no breast cancer causing gene
Post by: karajorma on December 24, 2008, 02:58:05 am
How on earth are you expecting the insertion of extra genes to happen from this?

Technically, he said 'alleles', which are variants of existing genes.

He said insertion of alleles. I assumed he meant insertion to the gene pool.

And my point still stands. I don't see how this is going to cause any more of that than happens naturally. Unless IVF results in more copying errors than naturally occur.
Title: Re: Child with no breast cancer causing gene
Post by: Martinus on December 24, 2008, 04:32:42 am
Whilst there is an acknowledged risk (by those familiar with the process on even an intermediate level) you are assuming a lot Mongoose. You are basically riding on humanity being amoral at best or immoral perhaps and just going to the most extreme of genetic specification. People don't work like that.

Religion still holds a big enough sway to ensure that this will creep along slowly. Only when it's either been proven to be so hit-and-miss to make it a bad decision or so advantageous that it unquestionably benefits people will religion push its advocates to 'ban' or endorse this. Also, the poorly educated are prone to jump on any bandwagon that is fed to them via the media and you can bet that enough conjectural horror-stories will be presented to ensure "our tax-money won't be spent on that!". Just look at the reaction to the large hadron collider; a fairly significant number of people were genuinely worried that the world was going to end.

At some point (probably not too far into the future) it is likely that we will have a good understanding of the nature and organisation of the human genome and will be able to manipulate it with more finesse than the current method. IVF's success rate is a big factor in how 'wasteful' of potential viable embryos this is (and I would like to interject to point out that the 'traditional' method of conception is responsible for countless numbers of embryos being discarded that seems to garner no similar moral dilemma) improvements here will reduce or remove the need for more than one fertilized egg.

We have almost reached the level of advancement that allows us to mitigate a large proportion of the chance involved in having to live with a drastic illness. I do not consider anyone who has not had to live with muscular dystrophy or a life-time's fear of hereditary disease to be able to claim that genetic modification should not happen without being biased. Yes, people with severe debilitating genetic diseases do have a potentially better quality of life now but at great expense to those who have to care for them who simply wanted a normal child. The quality of life they might enjoy now is mostly a consequence of living in a developed country; third world or developing countries have no infrastructure to support long-term survival or even survival with a minimal quality of life, babies are often simply discarded.

The possibility of not having to see suffering due to something that could feasibly be fixed rather than ignoring it because I've been told it's not the way of nature strikes me as by far the more moral choice. People are people and no law will ever be able to remove all possibility of someone using genetics for questionable reasons. I just trust that those among us who are vigilant and want it used for beneficial ends will be there to ensure that the chances of needless experimentation as close to zero as is possible.
Title: Re: Child with no breast cancer causing gene
Post by: Mongoose on December 24, 2008, 01:40:42 pm
Whilst there is an acknowledged risk (by those familiar with the process on even an intermediate level) you are assuming a lot Mongoose. You are basically riding on humanity being amoral at best or immoral perhaps and just going to the most extreme of genetic specification. People don't work like that.
My own experience of humanity leads me to have both great hope for our future and great doubt that we will be able to realize said future.  Our development as a society has given us great potential to further expand our horizons, but at the same time, we all-too-frequently manage to turn this potential against ourselves, to our own detriment.  (A certain sort of weapon comes to mind.)  I look at developments such as this in the field of genetics in the same light, tempered by my own ethical standards.  I think that this technology holds fantastic potential to alleviate suffering in many people, but I can also see many, many ways in which it can be misused to the detriment of society, which tempers my enthusiasm for it and leads to my urging of caution.

And if you'll allow me to swing off-topic just for a moment to address a particular point...

Quote
(and I would like to interject to point out that the 'traditional' method of conception is responsible for countless numbers of embryos being discarded that seems to garner no similar moral dilemma)
The fundamental ethical difference here is that procedures like IVF knowingly and willfully involve the destruction of embryos, whereas spontaneous abortions (miscarriages) occur without any knowledge or action by the parties involved.  The doctor performing IVF and the couple who is patronizing that doctor are fully aware that they will be discarding a number of spare embryos in the process.  In contrast, a couple normally having sex has no control over how (or if) the fertilized egg will develop.  As with any number of ethical issues (and such legal issues as murder, for that matter), the intent of the parties involved is as important as the end result.