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First 'three person baby' born using new method
- rcthompson 10y agoSounds like mother & father's nuclear DNA, injected into the nucleus of a 3rd party's donor's egg cell, which contains its own mitochondrial DNA. Since mtDNA is normally inherited 100% from the mother (since the mother's egg cell supplies the mitochondria to the embryo), if the mother has a mitochondrial genetic disease, 100% of her children would normally inherit it.
- nkrumm 10y agoYes-- the inheritance of mtDNA is maternal, but interestingly not 100% of her children will inherit the disease. This is because the mother will have a mix of mutated (diseased) mtDNA and wild-type (healthy) mtDNA in each of her cells, including her eggs. Some of the eggs will have close to all mtDNA mutated, but many will have a relatively low mutational burden. (This variation amongst the mother's cells and eggs is called heteroplasmy). Most mitochondrial genetic diseases have a heteroplasmy threshold (varying by gene/pathway, between 30-90% for many); when the overall burden in a fertilized egg is above this threshold, the disease is manifested in the offspring. Thus, another way to circumvent the transmission of mtDNA diseases is by using regular in vitro fertilization, and checking one of the cells at the 16 or 32 cell stage for their heteroplasmic content. Here are some references: Lightowlers, R. N., Taylor, R. W., & Turnbull, D. M. (2015). Mutations causing mitochondrial disease: What is new and what challenges remain? Science, 349(6255), 1494–1499. http://doi.org/10.1126/science.aac7516 http://doi.org/10.1126/science.aac7516 Taylor, R. W., & Turnbull, D. M. (2005). Mitochondrial DNA mutations in human disease. Nature Reviews Genetics, 6(5), 389–402. http://doi.org/10.1038/nrg1606 http://doi.org/10.1038/nrg1606 Smeets, H. J. M., Sallevelt, S. C. E. H., Dreesen, J. C. F. M., Die Smulders, C. E. M., & Coo, I. F. M. (2015). Preventing the transmission of mitochondrial DNA disorders using prenatal or preimplantation genetic diagnosis. Annals of the New York Academy of Sciences, 1350(1), 29–36. http://doi.org/10.1111/nyas.12866 http://doi.org/10.1111/nyas.12866
- rcthompson 10y agoInteresting. I wasn't aware of this, but it seems obvious in retrospect. Thanks for the info!
- ralfd 10y ago> checking one of the cells at the 16 or 32 cell stage I wonder: How is an embryo dealing with missing a cell at this early? Does this error compound after a few doublings (embryo is smaller)?
- pmalynin 10y agoAFAIK it shouldn't be issue. Some twins (identical twins) are created when a two cell organism detaches into two separate entities.
- aab0 10y agoIt doesn't seem to lead to any harms when done as part of preimplantation genetic diagnosis in general, so this specific case shouldn't be too bad.
- dnautics 10y agoThere is also the possibility that a sperm mitochondrion can be transmitted to the egg. Normally it's destroyed, but there's always exceptions in biology.
- mcphilip 10y agoAdditional background info from last year: http://www.bbc.com/news/health-31594856 http://www.bbc.com/news/health-31594856
- Shivetya 10y agoso science fiction of Alien Nation in a ways. so can they simply stock pile good genes and swap them out as necessary in the near future?
- grenoire 10y agoThat strays into the eugenics region. Not there yet; the moral and legal 'obstacles' will be present for a long while.
- wyager 10y agoI've never heard Eugenics defined in this way. I've only heard it used to mean selective planned breeding (as we do with livestock), but not intentional selective improvement of the parents' DNA.
- seangrogg 10y agohttps://en.wikipedia.org/wiki/History_of_eugenics https://en.wikipedia.org/wiki/History_of_eugenics Totally worth peeking into, it's interesting what many countries have considered, have attempted, and are continuing to ruminate on.
- sevenless 10y agoHitler got some of his worst ideas from the Eugenics Institute in California. Such as 'humanely' gassing undesirables and 'genetic defectives'. Eugenics, from Galton on, was considered progressive, enlightened, 'scientific' thought at the time.
- Symmetry 10y agoThe common thread in all the examples there is that choice are made for parents for the sake of society or "the race." I'm not familiar with Alien Nations so I can't speak to the OP but clearly not all genetic manipulation or screening is actually eugenics.
- deleted 10y ago[deleted]
- contingencies 10y agomtDNA is also very significant in historical migration studies... if anyone has a high level explanation of the global state of knowledge in this area I would love to see it ... trying to author a regionally focused ancient history book and piecing together the disparate pieces of supposed genetic evidence for various things is a task I am wholly unqualified for and would love some assistance with.
- misiti3780 10y agoThis book did a great job, but it might be outdated: https://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meaning/dp/0199205647 https://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meanin...
- Symmetry 10y agoIn another of Nick Lane's books he mentions compatibility between nuclear and mitochondrial DNA as a possible reason for variation in fertility in different species. If that's true I'd expect the 3-parent process to produce fewer pregnancies per fertilized egg than the normal 2-parent method which runs at around 50%.
- misiti3780 10y agowhich book was that ? Life Ascending?
- Symmetry 10y agoThat's what I was thinking, so if you think so too then probably.
- jerf 10y agoIt is often thought that humanity will leave no trace of its existence for the next civilization that will come, say, 20 million years from now. But I'd submit that unless something catastrophic happens very soon, one of the signs that "something" happened will be this sudden discontinuity in species history where suddenly the laws of genetics were thrown out the window for some reason, leaving its evidence both in the fossil record and in the attempts to plot out species trees based on genetic similarity. What today we are pleased to panic about in the "Holocene extinction" may in fact just be the opening act to an explosion of diversity, and the two events would not be distinguishable in the historical record.
- heydenberk 10y agoNotably, this prevents transmission of a disease that is "fatal to any baby conceived", which makes this as uncontroversial a case of a "designer baby" as I can imagine. After this, the ethics get much more complicated.
- afarrell 10y agoIt occurs to me: What are the ethical problems with designer babies?
- return0 10y agoIt occurs to me there aren't any; it's just a postmodern habit to treat every new technological possibility as an ethical problem first.
- maxerickson 10y agoRight, no quandary at all created by the possibility that mistakes and misunderstandings might lead to children with severe medical problems. Short, miserable lifetimes of suffering are a high cost for "improving the species", and they are a real possibility if the approach taken is to just try things that seem worth trying.
- rando444 10y agoSimilar risks are taken when two native people from different parts of the world have a baby together.
- maxerickson 10y agoThat's not true. Most genetic disorders are caused by receiving one or more defective copies of a gene. In the case of a single defective gene causing the disorder, it doesn't make a difference what gene the other parent has. In the case where multiple defective copies cause the disorder, the further apart two lineages are, the less likely it becomes that they will each have defective copies of the same gene. There's probably a higher chance of blood type incompatibilities, but that isn't a lifetime genetic disorder for the child, it just needs to be accounted for during the pregnancy.
- vermontdevil 10y agoInteresting they had to go to Mexico to perform this procedure.
- dethstar 10y agoFrom another article[0] >Neither method has been approved in the US, so Zhang went to Mexico instead, where he says “there are no rules”. [0]https://www.newscientist.com/article/2107219-exclusive-worlds-first-baby-born-with-new-3-parent-technique/ https://www.newscientist.com/article/2107219-exclusive-world...
- halhod 10y agothe original story, with more detail, is here https://www.newscientist.com/article/2107219-exclusive-worlds-first-baby-born-with-new-3-parent-technique/ https://www.newscientist.com/article/2107219-exclusive-world...
- deleted 10y ago[deleted]
- mlvljr 10y agoAny of them lesbians participated? :V
- alienallys 10y agoInshallah! What a wonderful magic, God bless these parents
- Raphmedia 10y agoAnd polygamy is stil illegal. I can father a child with my two girlfriends but cannot marry them both. Bah!
- spacehome 10y agoYou dodged a bullet there, trust me.
- roywiggins 10y agoCustody battles are complicated enough as it is...
- mizchief2 10y agoSo how long before 9 men can make a baby in a month?
- elevensies 10y agoIf I'm understanding correctly, this could be used for cloning if you could select two nuclei with non-overlapping chromosomes from a single person's sperm/eggs ... much easier to clone a man due the limits of egg extraction. back of the envelope: - each gamete has 1 of 2 choices for 23 chromosomes. - you need to find any two non-overlapping - probability of non-overlap is 0.5^23 for any pair - number of pairs equals (n choose 2) where n is number of gametes = n!/ (2 * (n - 2)!) = 0.5 * n * (n-1) = 0.5 * (n^2 - n) - to get a 50/50 chance of finding the right gametes: 0.5 = 0.5^23 * 0.5 * (n^2 - n), which is equivalent to: 0 = 0.5^23 * (n^2 -n) - 1 - solved via wolfram alpha, you would need to screen 2897 nuclei non-destructively to get a 50% chance of being able to generate a clone. I'm not aware if this is possible or not. But obviously if you can just replace chromosomes in-nucleus that is easier than screening, but if you can do that you don't really need this whole process since you can just replace the nucleus after IVF. If you could harvest a sex cell and do meiosis in a test tube, that would also get you your nuclei right away as well -- from 10 seconds of googling, I don't think we have this yet. I think when they screen zygotes they do it after some replication has happened, so the math really works against you if you need to combine sperm+egg pre-screen because you don't get the birthday paradox effect if you have to commit to your pairings beforehand, you'd need to huge egg supply as well.
- jack9 10y ago> But the science does raise ethical questions, including how any child from the technique might feel about having DNA from three people. That's not an ethical problem. Also, not a problem since, it's not any kind of problem to consider how kids might like PB&J sandwiches either.
- brian-armstrong 10y agoYou can't just brush it off and say it isn't a problem. Having 3 biological parents is incredibly rare and could have weird social effects for the child. It is an ethical concern if it affects how they relate to other people.
- mnw21cam 10y agoHow is this different to someone who has two parents, but has had a kidney transplant from a third person?
- c3534l 10y agoYeah, because fuck adoption. It only counts if it has your DNA, right?
- umanwizard 10y agoEvolutionarily, yes
- 4ad 10y agoPlease explain.
- umanwizard 10y agoYou only pass on your genes if you have a biological child, and that is important to some (but not all) people.
- shostack 10y agoOK, I'll bite... Having a child is a very personal decision. There are many factors, and for some, they may not feel adoption is right for them. It doesn't mean "fuck adoption," and it certainly doesn't give you the moral high ground to judge those who decide that having their own child is the right decision for them. And I'd add that three people having one child is a better ratio than two people having one for purposes of population control if you extrapolate out the math.
- FungalRaincloud 10y agoNot only that, but this is important research, whether we have too many people in the adoption system or not. The success of the human species relies on pushing our boundaries, every bit as much as it relies on taking care of one another.
- patrickg_zill 10y agoSo let's say in the future that the child needs a bone marrow donor. Does this cause any new wrinkles in finding a good match?
- mnw21cam 10y agoNot at all. 100% of the genomic DNA of the child comes from the two parents. This is where all the genes that determine rejection live. The mitochondria are actually a completely separate organism that live inside our cells and perform a useful function - they are often fairly diverse anyway.
- fasteo 10y agoNote that this will not stop some kids from getting these type of diseases, collectively known as mitochondrial myopathies. Some of them arise sporadically [1] In chronic progressive external ophthalmoplegia (CPEO) — a myopathy with the defining features of ophthalmoplegia and ptosis — Δ-mtDNAs are found only in muscle (implying that the deletion event occurred after fertilization in the muscle lineage of mesoderm). How do I know ? I have a mitocondrial myopathy (CPEO). My mother was perfectly healthy and all my brothers and sisters (5) are also ok. [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3959762/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3959762/