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Genetic Engineering Babies Essay Outline


The first study to modify the genes of a human embryo, conducted at Sun Yat-sen University in China, has caused a furious backlash. Nature and Science, the world’s most prestigious scientific journals refused to publish the study, at least partly on ethical grounds. Instead they publishedcommentaries calling for such research to be stopped. On Wednesday, the US government’s National Institutes of Health (NIH) restated their position that it will “not fund any use of gene-editing technologies in human embryos.” The NIH views such editing of the “germline” in human embryos as “a line that should not be crossed.” The stance will essentially stifle any research on gene editing in embryos in the US.

The ultimate goal of gene editing technologies is the capacity to make precise, controlled modifications to very specific areas of the genome. This would be a powerful ability. Gene editing unlocks access to an entirely novel way to fight disease which has been unreachable until now.

Scientists genetically modify human embryos in controversial world first

Around 7.9 million children each year are born with a serious birth defect that has a significant genetic contribution. If we could safely and easily correct these errors at the embryonic stage it would be possible to virtually eradicate this disease burden. In addition, 30% of all deaths worldwide are due to chronic diseases (such as heart disease, cancer, and diabetes) in those under 70. We all know of people who seem innately resistant to the perils of ageing and flourish well into their 80s and 90s. Gene editing could ensure we all have the best chance to live healthily into old age.

There are many challenges we must overcome to access the benefits of gene editing. The first and foremost is safety. Under agreed global research ethics standards, no experiments should be conducted where there is a high risk of harm to the participant, and a low chance of benefit. Gene editing is a long way from overcoming this barrier. Current techniques are imprecise, and lead to widespread damage to the genome. It would be highly unethical if a child was born whose genome was edited with current techniques.

Should we genetically engineer humans? – podcast

However, we can still perform important research with current gene editing technologies in ways which harm no one. The pioneering Chinese study was performed entirely on abnormal, unviable IVF embryos that could never result in a live birth. Gene editing techniques could be greatly advanced by experiments conducted entirely in petri dishes, with embryos that would otherwise be destroyed and in accordance with existing regulations. The UK has a comprehensive and well-established regulatory framework for embryo research, including provisions that only embryos under 14 days old be used. This framework has successfully guided research involving embryos for over two decades.

Many fear that such research will lead us on a path to “designer babies”. People shudder at the thought of parents picking and choosing the genes of their children, just as they pick and choose the accessories for their nurseries. And we have good reasons to be concerned about this prospect. Widespread access to gene editing technologies could harm children and damage the gene pool. Genes fashionable in one generation may prove to be harmful in the next. In addition, parental control of the gene pool could reduce valuable forms of diversity. If every parent picks the same immunity genes for their children, it may make them collectively as vulnerable to pathogens as 19th century Irish potatoes.

But a fear of designer babies should not distract us from the goal of healthy babies. We know that some genes are bad in nearly every conceivable environment. There is no possible way that the gene which causes Tay-Sachs disease - a disease in which children develop normally for six months and then become progressively deaf, blind, unable to swallow, and paralytic, before dying at four - will benefit future generations. We lose nothing by editing this gene out of the human lineage.

There is no reason why we couldn’t restrict the use of gene editing technologies to removing valueless genes like this. For over two decades we have successfully used IVF and pre-implantation diagnosis (PGD) in this way. Regulations restrict the use of these technologies to the prevention of disease. Similar regulations could restrict gene editing technologies to therapeutic uses.

Some see unpredictable consequences, rather than designer babies, as the key risk in crossing the line to edited embryos. They see meddling with our genome as inherently dangerous – no matter which genes we target. Just dipping our toes in the gene pool will cause large ripples. These ripples will cause chaotic and uncontrollable consequences. According to this view it would be far wiser not to dip our toes in at all.

But the gene pool is a violent ocean rather than a peaceful pond. The human germline is in a constant state of flux. Every new birth adds new genetic variants, and each death removes some. Many permitted human activities, like delaying paternity, add to this chaos by increasing the number of random mutations in the germline. Any ripples caused by targeted therapeutic gene editing will likely be dwarfed by other factors.

No matter what is done in the UK, the line to edited embryos and intentional germline modifications will be crossed soon. In the US, work can go ahead with funding from foundations, charities, companies or private individuals. China will race ahead. Others will likely follow. If we want gene editing research to be done in a responsible way, we need countries with good regulatory systems leading the charge. The UK is one such country, where the Human Fertilisation and Embryology Authority can provide reassurance that no research or application proceeds without proper evaluation.

Whoever first crosses the line to edited embryos will find a powerful new resource in the fight against disease. Like many resources there are risks associated with its use. Indeed the risks are very high. However ignoring the resource is also risky. We may needlessly subject future generations to an endless cycle of suffering and disease.

What we ought to do is use this resource responsibly. We should harness its power to achieve good ends and restrict its use for purposes that are bad. This will not be achieved by simply withdrawing from research. It’s time to mount a responsible expedition across the line to edited embryos and the UK should lead the way.

Chinese scientists say they've genetically modified human embryos for the very first time. The team attempted to modify the gene responsible for β-thalassaemia, a potentially fatal blood disorder, using a gene-editing technique known as CRISPR/Cas9. Gene editing is a recently developed type of genetic engineering in which DNA is inserted, replaced, or removed.

The team injected 86 embryos and 71 survived, of which 54 were genetically tested. This revealed that just 28 were successfully spliced, and that only a fraction of those contained the replacement genetic material. Analysis also revealed a number of 'off-target' mutations assumed to be caused by the technique acting in other areas of the genome. The results reveal serious obstacles to using the method in medical applications.

The scientists have tried to head off ethical concerns by using 'non-viable' embryos, which cannot result in a live birth, that were obtained from local fertility clinics. However, the work is very controversial, with some warning it could be the start of a slippery slope towards designer babies.

Below, some experts weigh-in with ethical questions and considerations.

Prof Robin Lovell Badge, Crick Institute, on the science: "The experiments reported by Junjiu Huang and colleagues (Liang et al) in the journal Protein Cell on gene editing in abnormally fertilised human embryos are, I expect, the first of several that we will see this year. There has been much excitement among scientists about the power of these new gene editing methods, and particularly about the CRISPR/Cas9 system, which is relatively simple to use and generally very efficient. The possibility of using such methods to genetically modify human embryos, and therefore humans, has been on the cards since these methods were first described, and recently these prospects have been brought to the attention of the public through several commentaries made by senior scientists and commentators, some of whom have called for a moratorium to halt any attempts."

Dr Yalda Jamshidi, Senior Lecturer in Human Genetics, St George's University Hospital Foundation Trust, said: "Inherited genetic conditions often result because the function of a gene is disrupted. In theory replacing the defective gene with a healthy one would be the ideal solution. This type of treatment is what we call gene therapy and researchers have been working on developing techniques to accomplish this for many years.

"Techniques to correct defective genes in 'non-reproductive' cells are already at various stages of clinical development and promise to be a powerful approach for many human diseases which don't yet have an effective treatment. However, altering genes in human embryos can have unpredictable effects on future generations. Furthermore the study by Huang et al showed that the although the CRISPR/Cas9 technique they used can work in the embryo, it can miss the target in the gene and is too inefficient.

"Future research on the technique may improve the accuracy and efficiency, however scientists still don't fully understand the role of the DNA, and all of its genes. Therefore it is impossible to assess the risks from mis-targeted changes in the DNA sequence, which would affect both the treated embryo and any future generations."

Prof Shirley Hodgson, Professor of Cancer Genetics, St George's University of London, said: "I think that this is a significant departure from currently accepted research practice. This is because any manipulation of the germline of human embryos is potentially heritable. Can we be certain that the embryos that the researchers were working on were indeed non-viable? In the past all the gene therapy research that has been approved by regulatory bodies has been somatic, not germline, because of the potentially unpredictable and heritable effects of germline research. The fact that these researchers found that there were a number of "off target" mutations resulting from the technique they used is clearly a worry in this context. Any proposal to do germline genetic manipulation should be very carefully considered by international regulatory bodies before it should be considered as a serious research prospect. This is because of the obvious concerns about the heritability of the genetic alterations induced, and the way in which such research could spread from work on "non-viable" embryos, to work on viable ones once this type of research had been accepted in principle by international regulatory bodies."

Prof Darren Griffin, Professor of Genetics, University of Kent, said: "Given the widespread use of the CRISPR/Cas9 system, such announcement was inevitable, sooner rather than later. We clearly have a lot of thinking to do. Germline manipulation is currently illegal in the UK but the question is bound to be asked whether this should change, especially if the safety concerns are allayed."

Associate Professor Peter Illingworth is Medical Director at IVFAustralia: "This is a fascinating piece of experimental science. Using abnormally-fertilised human embryos (I.e. With three sets of DNA instead of two), they have studied whether the a human gene can be modified. They have demonstrated that, in some embryos, but not all, they can change the abnormal human gene. They also find that other genes are affected which may be a serious concern. What they have shown is that it is technically possible, not that it is practically feasible or safe."

Further information:

http://www.sciencemediacentre.org/expert-reaction-to-the-application-of-genome-editing-techniques-to-human-embryos/

http://www.smc.org.au/expert-reaction-worlds-first-genetic-modification-of-human-embryos-reported-protein-cell/


Story Source:

Materials provided by ResearchSEA. Note: Content may be edited for style and length.


Journal Reference:

  1. Puping Liang, Yanwen Xu, Xiya Zhang, Chenhui Ding, Rui Huang, Zhen Zhang, Jie Lv, Xiaowei Xie, Yuxi Chen, Yujing Li, Ying Sun, Yaofu Bai, Zhou Songyang, Wenbin Ma, Canquan Zhou, Junjiu Huang. CRISPR/Cas9-mediated gene editing in human tripronuclear zygotes. Protein & Cell, 2015; DOI: 10.1007/s13238-015-0153-5


Cite This Page:

ResearchSEA. "World's first genetic modification of human embryos reported: Experts consider ethics." ScienceDaily. ScienceDaily, 24 April 2015. <www.sciencedaily.com/releases/2015/04/150424122312.htm>.

ResearchSEA. (2015, April 24). World's first genetic modification of human embryos reported: Experts consider ethics. ScienceDaily. Retrieved March 13, 2018 from www.sciencedaily.com/releases/2015/04/150424122312.htm

ResearchSEA. "World's first genetic modification of human embryos reported: Experts consider ethics." ScienceDaily. www.sciencedaily.com/releases/2015/04/150424122312.htm (accessed March 13, 2018).

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