Successful Correction of Genetic Problems In Mice Before Birth Raises Hopes of Similar Treatments For Humans (theguardian.com) 26
An anonymous reader quotes a report from The Guardian: Gene editing to correct faulty DNA in human embryos has taken a step closer to becoming a reality, with scientists showing it is possible to correct genetic problems in mice before they are born. Researchers used a form of the gene-editing tool Crispr-Cas9 to introduce a mutation into a gene that would otherwise cause lethal liver failure in mice. While the approach has previously been shown to work in mice after birth, the latest study showed it was also possible to make the all-important tweak before they were born. Writing in the journal Nature Medicine, a team of researchers in the US report how they conducted a series of experiments to explore the use of gene editing in mouse fetuses using a modified form of Crispr that can alter single "base pairs" -- the molecules that couple up to form the rungs of the DNA double helix -- but only cuts one strand of DNA when making a change.
After showing it was possible to make a change at a particular spot in the DNA of liver cells in mouse fetuses, the team focused on a condition known as hereditary tyrosinemia type 1. This is a genetic disease that prevents the body from breaking down an amino acid called tyrosine as it should, and can cause death if left untreated. The team took mice with a genetic mutation that produced a similar condition to hereditary tyrosinemia type 1 and bred them, with the mothers kept on a drug called nitisione. The team then injected 26 of the fetuses with a virus carrying the genetic instructions for making the gene-editing tool, and 27 of them with the same virus but without information for the tool. After birth the baby mice no longer received the drug, and the team watched what happened. "In the non-treated mice, they all died by 21 days of life," said Dr William Peranteau, a pediatric and fetal surgeon at the Children's Hospital of Philadelphia who co-led the study. "However, those that had been treated were able to survive until the end of the study at three months, and looked very similar to another group that had not been injected with anything and were kept on the drug. No gene editing was seen in the mothers who had given birth to the mice.
After showing it was possible to make a change at a particular spot in the DNA of liver cells in mouse fetuses, the team focused on a condition known as hereditary tyrosinemia type 1. This is a genetic disease that prevents the body from breaking down an amino acid called tyrosine as it should, and can cause death if left untreated. The team took mice with a genetic mutation that produced a similar condition to hereditary tyrosinemia type 1 and bred them, with the mothers kept on a drug called nitisione. The team then injected 26 of the fetuses with a virus carrying the genetic instructions for making the gene-editing tool, and 27 of them with the same virus but without information for the tool. After birth the baby mice no longer received the drug, and the team watched what happened. "In the non-treated mice, they all died by 21 days of life," said Dr William Peranteau, a pediatric and fetal surgeon at the Children's Hospital of Philadelphia who co-led the study. "However, those that had been treated were able to survive until the end of the study at three months, and looked very similar to another group that had not been injected with anything and were kept on the drug. No gene editing was seen in the mothers who had given birth to the mice.
Re:Yes but... (Score:1)
I see Mike Pence left you alone again, Mr.Prez... (Score:2)
Put down the koolaid. :)
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I can think of many reasons. The article stated that they were interested in diseases that may be fatal before or shortly after birth. So waiting longer would certainly be a bit of a problem.
But many genetic flaws cause the body to grow abnormally. Fixing the genetic flaw won't repair what has already grown incorrectly.
One genetic flaw that I'm familiar with is Myotonic Muscular Dystrophy. It is an interesting one that has a nearly unique cause that should make it a candidate for being among the first to be
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But wouldn't it be so much easier and safer to *screen* embryos for known genetic defects, rather than patch them with CRISPR?
The real potential for this technique is to introduce new gene alleles that are not present in the parents.
Yes that is terrifying, but with proper regulation, imagine the potential!
If applied broadly, it could raise the socioeconomic status for the children of the most disadvantaged groups, leading to a more equitable society.
Alternatively, given to those who can pay lots of money, i
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Oh dear AC, no need to be so melodramatic.
We are talking about pre-implantation screening of embryos, clumps of cells in a petri dish.
This implies IVF, which has its risks, but easier and safer than in-utero gene editing, surely?
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Screening certainly helps, but the problem is that by the time there is enough material to take a sample and screen it you are in a position where the only options are carry to term or have an abortion. Having a third option, correction, is highly desirable.
This of course raises questions about what is considered a defect that needs to be cured. People have abortions for stuff like cleft palette.
I don't think it will really help socioeconomically disadvantaged children though. It won't help the parents find
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Screening certainly helps, but the problem is that by the time there is enough material to take a sample and screen it you are in a position where the only options are carry to term or have an abortion.
Not at all. See Preimplantation genetic diagnosis [wikipedia.org].
It won't help the parents find time to read to their kid, it won't make their local school any better, won't buy them books and computers,
Adoption studies show these things are unimportant compared to genetics. One study found that kids with books in the house did better, regardless of whether the parents had time to read them. i.e. a kid does better not because his parents read to him, but because he has the genes of the sort of people who read to their kids. If there are any real parenting effects, they will be reduced in the next generation. We are talking about a multi-generational pr
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Please forgive my lack of understanding on this subject (and, really, my unwillingness to spend an inordinate amount of time finding an answer when some of you smart people can just answer quickly). In this kind of research is the genetic problem one that would be passed to future generations and if so, does the âoefixâ also correct that? Thanks!
Yes obviously genetic problems are often passed from parents to the child(usually faulty recessive genes) though disorders can form due to other issues but it is mainly hereditary problems(E.G. Asthma, skin problems, etc). However what this could potentially do is stop the disorder in its tracks. If you fix the issues with the child when they are merely a zygote you in turn correct their DNA before they fully form. Not only would this person not have the disorder but this would cause a cascading effect b
Recursive self-improvement (Score:2)
This is a fantastic development. Humanity has been plagued with genetic health issues that continue to propagate because they aren't significant enough prevent it. This could lead to each generation of humans becoming increasingly healthier. If people want to cry about "playing God," fine by me. However, I would like to see future generations never have the myriad of defects that fundamentally alter their lives. Also no more glasses. :)