Sunday, November 12, 2017

Clinical somatic gene editing could be a reality, human enhancement is still a distant shot says the Bioethics committee

https://geneticliteracyproject.org
It is nearly four years ago, scientists reported that clustered regularly interspaced short palindromic repeats-Cas9 (CRISPR-Cas9) technology can enable precise and efficient genome editing in living eukaryotic cells. Since then, scientists are looking for feasibility of successful somatic and germline editing to eliminate many devastating genetic diseases. But, it also comes with a thorny international debate as it opens the door to designer babies and engineered humans.

On August 2, 2017, scientists at the Oregon Health & Science University reported that they had succeeded for the first time in United States in correction of the dominant MYBPC3 mutation that causes a late-onset familial version of hypertrophic cardiomyopathy using CRISPR/Cas9. 


What is DNA editing


One day after this paper was published in Nature, the American Society of Human Genetics (ASHG), and 11 organizations including representatives from the UK Association of Genetic Nurses and Counsellors, Canadian Association of Genetic Counsellors, the International Genetic Epidemiological Society, and the US National Society of Genetic Counselors, as well as the ASHG,  published a joint statement in August concentrating on the prospects for germline alteration. 

The statement as published in the AmericanJournal of Human Genetics, again reiterated that clinical use of germline editing is not allowed at present- these are genetic changes that would be in every cell of a resulting baby and be passed on to future generations, viewed as ‘ethical violation’ by many.  
On the plus side, it provides the only hope for some parents who are carriers of genetic diseases with their best or most acceptable option for having genetically related children who are born free of these diseases. 

Germline somatic editing has already entered clinical trials for non-heritable applications, for treating or preventing diseases or disabilities at this time.

There are three important differences between the two approaches.
1.     Somatic therapies target genes in specific types of cells (lung cells, skin cells, blood cells, etc), while germline modifications, applied to embryos, sperm or eggs, alter the genes in all the resultant person’s cells.
2.      Somatic cell modifications are not biologically transferred to next generations, so it only affects one individual.  Germline editing would be inheritable, have greater impact as it would affect the generations to come.
3.     Clinical trials involving somatic cell therapies are around over two decades now, while human germline editing studies have only just begun this year.

There are a host of unanswered ethical and scientific dilemmas, around the procedure but it does not deny the prospects of germline editing, if the ethical and policy guidelines are met. More stringent regulations would need to be in place, to ensure safety and efficacy when tinkering with human nature

Currently, heritable germline editing is not permissible in the United States.  It is only allowed for purpose of research as the statement published in the American Journal of Human Genetics after 16 months of deliberation, “Currently, there is no reason to prohibit in vitro germline genome editing on human embryos and gametes, with appropriate oversight and consent from donors, to facilitate research on the possible future clinical applications of gene editing.”

It suggested that research into genetic modifications should continue as long as it doesn’t lead to a pregnancy.

This ASHG statement is the second set of recommendations issued in 2017, following an exhaustive 300 pages NationalAcademy of Sciences, Engineering, and Medicine (NASEM) document “Human Genome Editing: Science, Ethics, and Governance.” 

The NASEM statement is more wide and covers somatic gene editing, but both the statements expressed reservations currently on using germline editing for creating ‘engineered humans’, but did not deny the possibility of it in future.

Both statements also called for public funding, for manipulating human embryos and fetuses for research, arguing that without funds the research may move offshore, where less stringent regulations and transparency prevails and that may result in rogue experimentation.

Human genome editing is already widely used in basic research and is in the early stages of development and trials for clinical applications that involve non-heritable (somatic) cells.

The Chinese and U.K laws are already in place.

Biologist Paul Knoepfler estimates that genetically modified people will no longer be a science fiction fantasy; it's a likely future scenario. Within fifteen years, scientists could use the gene editing technology CRISPR to make certain "upgrades" to human embryos — from altering physical appearances to eliminating the risk of auto-immune diseases. 

As Victor Hugo said, “there is nothing more powerful than an idea whose time has come.” So, now it’s a question of “when”, instead of “never”.
Here is a video by Françoise Baylis, a philosopher and professor at Dalhousie University, is one of the foremost voices among bioethics scholars worldwide.

Her mission is to foster an inclusive dialogue on what should and should not be allowed through gene editing. As the consequences of these decisions will affect future generations





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