Scientists Seek Ban on Method of Editing the Human Genome Photo A group of leading biologists on Thursday called for a worldwide moratorium on use of a new genome-editing technique that would alter human DNA in a way that can be inherited. The biologists fear that the new technique is so effective and easy to use that some physicians may push ahead before its safety can be assessed. “You could exert control over human heredity with this technique, and that is why we are raising the issue,” said David Baltimore, a former president of the California Institute of Technology and a member of the group whose paper on the topic was published in the journal Science. Ethicists, for decades, have been concerned about the dangers of altering the human germline — meaning to make changes to human sperm, eggs or embryos that will last through the life of the individual and be passed on to future generations. The technique holds the power to repair or enhance any human gene. There are two broad schools of thought on modifying the human germline, said R. Photo
Aux origines de CRISPR Il est bien connu que les meilleurs vulgarisateurs sont souvent ceux-là mêmes qui ont fait les découvertes. Le bouquin d’Einstein et Infeld sur la relativité est par exemple l’une des meilleures expositions du sujet pour le grand public. A Crack in Creation, le premier livre sur CRISPR écrit par l’une de ses deux co-découvreuses, Jennifer Doudna, associée à Samuel Sternberg, un chercheur de son équipe, entre dans cette catégorie. On comprend vraiment grâce à eux le mécanisme de cette nouvelle biotechnologie ainsi que ses implications. CRISPR, cette technologie qui bouleverse la biotechnologie (pour Clustered Regularly Interspaced Short Palindromic Repeats, c’est-à-dire – pour autant que ce soit plus clair en français – « Courtes répétitions palindromiques groupées et régulièrement espacées »), est une technique de manipulation du génome qui consiste – pour le dire trop simplement – à faire des modifications au niveau de l’ADN (voir la vidéo explicative de Nature). Qu’apprend-on ?
Designer Babies: Gene-Editing and the Controversial Use of CRISPR The concept of designer babes has been discussed a lot in recent months after a Chinese doctor claimed he helped create two babies with modified genes. This has sparked various debates on the ethics of genetic manipulation and the future of genetics. The term 'designer baby' refers to a baby that has been given special traits through genetic engineering. Genetic editing is the process of making changes to the genetic code (DNA). A new technique, called CRISPR (clustered regularly interspaced short palindromic repeats) has allowed scientists to cheaply and very rapidly alter the genome of almost any organism. Genetic editing in humans is a controversial topic, but not all forms of human genetic manipulation are in question. CRISPR is a tool with immense potential to create better crops and livestock, manufacture new drugs, eliminate pests, and treat critical illnesses. For this reason, the altering of somatic cells for the treatment of diseases is not generally regarded as controversial.
Human Embryo Editing Sparks Epic Ethical Debate In a world first, Chinese scientists have reported that they have used powerful gene-editing techniques to modify human embryos. Their paper, published in the Beijing-based journal Protein & Cell on April 18, came as no surprise to the scientific community, but it has ignited a wide-ranging debate about what types of gene-editing research are ethical. The publication also raises questions about the appropriate way to publish such work. In the paper, researchers led by Junjiu Huang, a gene-function researcher at Sun Yat-sen University in Guangzhou, describe how they used a system of molecules called CRISPR/Cas9, known for its ease of use, to cut DNA in human embryos and then attempted to repair it by introducing new DNA. In a deliberate attempt to head off ethical concerns, the team used non-viable embryos obtained from fertility clinics, in which eggs had been fertilized by two sperm and so could not result in a live birth. Modifying human embryos is legal in China and in many US states.
Development of a fast and easy method for Escherichia coli genome editing with CRISPR/Cas9 | Microbial Cell Factories | Full Text Compared to other CRISPR-based genome modification system, our one-plasmid system has the advantage of fast and easy operation with high efficiency. A simple comparison is summarized in Table 4 to illustrate difference of this technique compared with several recently developed methods. Information in this table is by no means accurate and subjective, and some description is by estimation. Due to the simplicity of one plasmid without any other supplemental DNA material, the experiment process is simple and less time consuming than other methods, only takes 3 days to complete. The method also has an advantage for editing of multiple loci. High throughput and automatic genomic editing is one highly desired technique by molecular biologists [24, 25]. Colony PCR was used to identify successfully edited clones based on the size of PCR products in this work.
Comment l'Homme se distingue | Le blob, l'extra-média Episode 2 Comment l’Homme se distingue Commentaires en voix-off en jaune Générique 3D Dans la cellule, au cœur du noyau, le chromosome est constitué d’un long fil d’ADN. Ce fil supporte les quelques dizaines de milliers de gènes qui composent la carte d’identité de notre espèce. Mais la vie nécessite un choix parmi ces gènes, une lecture épigénétique sélective qui accompagne chacune de nos cellules, de la première, le zygote, jusqu’à notre mort. Plastiline L’épigénétique a progressé en comparant de vrais jumeaux : alors qu’ils partagent strictement le même génome, les jumeaux ne sont jamais parfaitement identiques. Titre Intro Deborah Bourc’his Donc au sein d'une ruche les ouvrières et les reines en faite sont des jumelles elles ont un capital épigénétique elles ont exactement les mêmes gènes puisqu'elles proviennent toutes de la même mère. Alors comment est-ce qu'on atteint cette diversité à partir de mêmes gènes hein, ce sont des jumelles je le rappelle. Deborah Bourc’his Commentaire Schéma
New Discovery Moves Gene Editing Closer to Use in Humans A tweak to a technique that edits DNA with pinpoint precision has boosted its ability to correct defective genes in people. Called CRISPR, the method is already used in the lab to insert and remove genome defects in animal embryos. But the genetic instructions for the machinery on which CRISPR relies—a gene-editing enzyme called Cas9 and RNA molecules that guide it to its target—are simply too large to be efficiently ferried into most of the human body’s cells. This week, researchers report a possible way around that obstacle: a Cas9 enzyme that is encoded by a gene about three-quarters the size of the one currently used. The finding, published on 1 April in Nature, could open the door to new treatments for a host of genetic maladies (F. A. “There are thousands of diseases in humans associated with specific genetic changes,” says David Liu, a chemical biologist at Harvard University in Cambridge, Massachusetts, who was not involved in the latest study.
En images : ils coupent de l'ADN grâce à CRISPR ! Des chercheurs japonais ont réussi à filmer les ciseaux moléculaires CRISPR-Cas9 en train de couper de l'ADN. Ce travail apporte de nouvelles informations sur le processus qui permet de modifier des génomes dans les laboratoires utilisant ces techniques de génie génétique. Ce qu'il faut retenir La vidéo, ou, plus exactement, le GIF animé, apporte de nouvelles informations sur le processus au niveau moléculaire.CRISPR-Cas9 est une technique d'édition génomique qui permet de modifier facilement les génomes animaux ou végétaux.Des chercheurs japonais ont filmé le clivage de l'ADN en temps réel.La vidéo, ou, plus exactement, le GIF animé, apporte de nouvelles informations sur le processus au niveau moléculaire.CRISPR-Cas9 est une technique d'édition génomique qui permet de modifier facilement les génomes animaux ou végétaux. Les ciseaux moléculaires CRISPR-Cas9 font à nouveau parler d'eux... Cas9 est une protéine qui a une activité de nucléase, c'est-à-dire qu'elle peut couper l'ADN.
Intron RNA sequences help yeast cells to survive starvation RNA molecules that are newly transcribed from DNA contain intron and exon sequences. Introns are excised through a process called RNA splicing, during which the remaining exon sequences are joined together (ligated) to form mature messenger RNA, which is then translated into proteins. RNA splicing releases a lariat-shaped intron that is rapidly converted (debranched) to a linear form and degraded. Much of what we know about the molecular machinery — the spliceosome and its associated factors — and the mechanisms of splicing has come from genetic and biochemical experiments using baker’s yeast (Saccharomyces cerevisiae). Although the splicing machinery has been highly conserved during evolution, gene architecture is complex and varies across organisms. Parenteau et al. and Morgan et al. shine new light on the role of introns. The authors then created a small DNA molecule containing the gene that produces one of the introns that accumulates during the stationary phase.
Environmental Factor - February 2021: Precision environmental health brings nuance to disease prevention This month, I am excited to share with you excerpts from my recent conversation with Cheryl Walker, Ph.D., a long-time NIEHS grant recipient who directs the Center for Precision Environmental Health at Baylor College of Medicine. In future months, look for more interviews like this one. I want to increase opportunities for collaboration, which starts with conversation and the exchange of ideas. (Image courtesy of NIEHS) Her research into how chemical exposure during early life can interact with an individual’s epigenome and influence later-life health and disease is at the cutting edge of environmental health science. Walker’s innovative research approaches and desire to promote collaboration dovetail with my core leadership values, outlined in my inaugural Director’s Corner column. She is a member of the NIEHS Toxicant Exposures and Responses by Genomic and Epigenomic Regulators of Transcription (TaRGET) consortium. Individual susceptibility to disease Take cancer as an example.