Genome-edited Embryos

----Technic & Moral

5141309059 应言

Scientists combined up to six rhesus(恒河猴 ) monkey embryos to produce three animals. Embryos were placed into female rhesus monkeys.

American Scientists Create The World's First Genetically Engineered Monkeys

Chinese Team Reports Gene-Editing Human Embryos• Studied the ability of the CRISPR/Cas9 system to edit the gene

called HBB, which encodes the human β-globin protein. Mutations in the gene are responsible for β-thalassaemia.

• 86 injected, 71 survived, 28 were successfully spliced, only a fraction of those contained the replacement genetic material.

• A surprising number of ‘off-target’ mutations

CRISPR/CAS9• Clustered Regularly Interspersed Short Palindromic Repeats• 规律成簇间隔短回文重复• CRISPR associated (Cas )---CRIPSR 关联基因

CRISPR Gene Editing to Be Tested on People by 2017, Says Editas• Treat one form of a rare eye

disease called Leber congenital amaurosis, which affects the light-receiving cells of the retina

• Editas plans to deliver the CRISPR technology as a gene therapy.

• Bosley said in order to treat LCA, the company intends to delete about 1,000 DNA letters from a gene called CEP290 in a patient’s photoreceptor cells.

Countries Policies—vary wildly across the world• Prohibited by laws : 40 , most visible in western Europe, where

15 of 22 nations prohibit the modification of the germ line. • Germany strictly limits experimentation on human embryos• Many countries do not have explicit legislation in place

permitting or forbidding genetic engineering in humans • In China, Japan, Ireland and India, only unenforceable

guidelines restrict genome editing in human embryos.

NIH reiterates ban on editing human embryo DNA• A 1996 US law bans the government from funding work that

destroys human embryos or creates them for the purposes of research.

• Later rules allowed research in human embryonic stem-cell lines.

• The NIH says that the law’s wording would probably prohibit funding for work in a non-viable human embryo

• Embryo-- anything derived from “fertilization, parthenogenesis, cloning, or any other means”

The Hinxton Group

• “we all agreed that while this technology has tremendous value to basic research and enormous potential for somatic clinical uses, it is not sufficiently developed to consider human genome editing for clinical reproductive purposes4 at this time.”

Experts

Pros • Eliminate diseases • Human advancement• “The human genome is not perfect,” says John Harris, a

bioethicist at Manchester University, in the U.K. “It’s ethically imperative to positively support this technology.”

• Provide people with favorable versions of genes, making DNA edits that would act as vaccines against some of the most common diseases we face today

• MIT Technology Review http://www.technologyreview.com/featuredstory/535661/engineering-the-perfect-baby/

• Unpredictable effects on future generations. Any human embryo altered with CRISPR today would carry the risk that its genome had been changed in unexpected ways• Ethical implications of altering genes that will be passed to

future generations of humans.• Necessity?--Few clinical situations in which editing would be

the only way to prevent the passage of a genetic disease from parent to child.

a process that adds about $4,000 to the cost of a fertility procedure

Cons

Contrary Arguments (depends on your belief)

Humanism: 1) Let's play god.(We are evolved from apes) 2) Our lives belong to ourselves, so we can change it if we want. 3) The quality of our body life is the most important

Christian: 1) Only god can create us 2) Our body is holy and shouldn't be changed at will 3) Our soul is the above all

Utilitarianism Deontology

Arguments• Should genome editing be allowed in basic research involving

human sperm, eggs and embryos?• Should only embryos left over from in vitro fertilization be

used in genome-editing research or may embryos be specifically created for research?

• What safety and efficacy thresholds need to be met before the use of genome editing in human reproductive applications could be considered?

• If such thresholds are met, what uses for genome editing in human reproductive applications might be permissible?

Questions

• Voluntary or forced• (dignity and independence of humans)• Cure disease or create perfection• (the individuality of humans)• Vanity or real improvement• (Really do good to human beings?or just

another way to show off??Then what about the balance of the whole nature?)

• …………

Actions • Establish a model regulatory framework that

could be adopted internationally• “Key to all discussion and future research is making a clear

distinction between genome editing in somatic cells and in germ cells.” –Don’t edit the human germ line

• Design tools and methods to enable inclusive and meaningful deliberation.

Reference-Nature• Where in the world could the first CRISPR baby be born?• http://www.nature.com/news/where-in-the-world-could-the-first-crispr-baby-be-

born-1.18542• Genome editing: 7 facts about a revolutionary technology• http://www.nature.com/news/genome-editing-7-facts-about-a-revolutionary-

technology-1.18869?WT.mc_id=SFB_NNEWS_1508_RHBox• Chinese scientists genetically modify human embryos• http://www.nature.com/news/chinese-scientists-genetically-modify-human-embryos-

1.17378• Don’t edit the human germ line• http://www.nature.com/news/don-t-edit-the-human-germ-line-1.17111• CRISPR: A path through the thicket• http://www.nature.com/news/crispr-a-path-through-the-thicket-1.18748• NIH reiterates ban on editing human embryo DNA• http://www.nature.com/news/nih-reiterates-ban-on-editing-human-embryo-dna-

1.17452

Reference-MIT Technology Review• CRISPR Gene Editing to Be Tested on People by 2017, Says

Editas• http://www.technologyreview.com/news/543181/crispr-gene-

editing-to-be-tested-on-people-by-2017-says-editas/• Engineering the Perfect Baby• http://www.technologyreview.com/featuredstory/535661/

engineering-the-perfect-baby/• How to (Really) Engineer a Human Baby• http://www.technologyreview.com/news/543541/how-to-really-

engineer-a-human-baby/• Chinese Team Reports Gene-Editing Human Embryos• http://www.technologyreview.com/news/536971/chinese-team-

reports-gene-editing-human-embryo/

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