Monday, November 26, 2018

Generation CRISPR?



Very strange. This guy left his university a few years ago to concentrate on this research. Are his claims real?
Genome-edited baby claim provokes international outcry (Nature News)

The startling announcement by a Chinese scientist represents a controversial leap in the use of genome-editing.

A Chinese scientist claims that he has helped make the world's first genome-edited babies — twin girls who were born this month. The announcement has provoked shock, and some outrage, among scientists around the world.

He Jiankui, a genome-editing researcher from the Southern University of Science and Technology of China in Shenzhen, says that he implanted into a woman an embryo that had been edited to disable the genetic pathway that allows a cell to be infected with HIV.

In a video posted to YouTube, He says the girls are healthy and now at home with their parents. Genome sequencing of their DNA has shown that the editing worked, and only altered the gene they targeted, he says.

...
See also MIT Technology Review:
The Chinese scientist who claims he made CRISPR babies is under investigation

He, who led that effort, later released a video statement in which he said that healthy twin girls, Lulu and Nana, had been born “a few weeks ago.”

He said the girls had been conceived using IVF but that his team had added “a little protein and some information” to the fertilized eggs. That was a reference to the ingredients of CRISPR, the gene-editing technology he apparently employed to delete a gene called CCR5.

The claim set off a wave of criticism in China and abroad from experts who said the experiment created unacceptable risks for a questionable medical purpose. Feng Zhang, one of the inventors of CRISPR, called for a moratorium on its use in editing embryos for IVF procedures.

Documents connected to the trial named the study’s sponsors as He along with Jinzhou Qin and said it was approved by the ethics committee of HarMoniCare Shenzhen Women and Children’s Hospital.

On Sunday, the Shenzhen City Medical Ethics Expert Board said it would begin an investigation of He’s research and released a statement saying that HarMoniCare “according to our findings … never conducted the appropriate reporting according to requirements.” The former medical director of the private hospital, Jiang Su-Qi, told Southern Capital News he had no recollection of approving He’s research while he was on its ethics committee.

...

The president of He’s university called an emergency gathering of researchers connected to the project. “This has nothing to do with SUST, the research wasn’t conducted at SUST,” said SUST president Chen Shiyi, according to Chinese media reports. According to the school’s biology department, the research “seriously violates ethical and academic standards and regulations.” ...

Regarding the use of CRISPR in human reproduction, here is my tweet from earlier today:

Here is what I wrote in 2014 about editing vs selection of embryos:

... the distinction between embryo selection -- the parents get a baby whose DNA originates from them, but the "best baby possible" -- and active genetic editing, which can give the child genes that neither parent had.

The movie GATTACA focuses on selection -- the director made a deliberate decision to eliminate reference to splicing or editing of genes. (Possibly because Ethan Hawke's character Vincent would have no chance competing against edited people.)

At SCI FOO, George Church seemed confident that editing would be an option in the near future. He is convinced that off-target mutations are not a problem for CRISPR. I have not yet seen this demonstrated in the literature, but of course George knows a lot more than what has been published. (Warning: I may have misunderstood his comments as there was a lot of background noise when we were talking.)

One interesting genetic variant (Lrp5?) that I learned about at the meeting, of obvious interest to future splicers and editors, apparently conveys an +8 SD increase in bone strength!

My views on all of this:
... given sufficient phenotype|genotype data, genomic prediction of traits such as cognitive ability will be possible. If, for example, 0.6 or 0.7 of total population variance is captured by the predictor, the accuracy will be roughly plus or minus half a standard deviation (e.g., a few cm of height, or 8 IQ points). The required sample size to extract a model of this accuracy is probably on the order of a million individuals. As genotyping costs continue to decline, it seems likely that we will reach this threshold within five years for easily acquired phenotypes like height (self-reported height is reasonably accurate), and perhaps within the next decade for more difficult phenotypes such as cognitive ability. At the time of this writing SNP genotyping costs are below $50 USD per individual, meaning that a single super-wealthy benefactor could independently fund a crash program for less than $100 million.

Once predictive models are available, they can be used in reproductive applications, ranging from embryo selection (choosing which IVF zygote to implant) to active genetic editing (e.g., using powerful new CRISPR techniques). In the former case, parents choosing between 10 or so zygotes could improve their expected phenotype value by a population standard deviation. For typical parents, choosing the best out of 10 might mean the difference between a child who struggles in school, versus one who is able to complete a good college degree. Zygote genotyping from single cell extraction is already technically well developed [25], so the last remaining capability required for embryo selection is complex phenotype prediction. The cost of these procedures would be less than tuition at many private kindergartens, and of course the consequences will extend over a lifetime and beyond.

The corresponding ethical issues are complex and deserve serious attention in what may be a relatively short interval before these capabilities become a reality. Each society will decide for itself where to draw the line on human genetic engineering, but we can expect a diversity of perspectives. Almost certainly, some countries will allow genetic engineering, thereby opening the door for global elites who can afford to travel for access to reproductive technology. As with most technologies, the rich and powerful will be the first beneficiaries. Eventually, though, I believe many countries will not only legalize human genetic engineering, but even make it a (voluntary) part of their national healthcare systems [26]. The alternative would be inequality of a kind never before experienced in human history.
Here is the version of the GATTACA scene that was cut. The parents are offered the choice of edited or spliced genes conferring rare mathematical or musical ability.


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