It's been a fortnight since the genetically modified twins were born in the city of Shenzhen in China. Yet, still the controversy of the event continues. The basis of this news story from a fortnight ago was that a Chinese scientist named Jiankui He, has altered the genetics of a set of twins by the process of CRISPR.
For those not of a scientific background, CRISPR is an up and coming process still in its infancy. I'll liken to as a pair of biological scissors that can cut out a chosen gene from DNA. CRISPR can even add on proteins to the DNA chain to prevent that line of genetics from being expressed. Or even force the body to constantly make that part of DNA. All parts of CRISPR is useful for different situations. At the moment, scientists are using the process to either remove undesirable mistakes from cells or promote a certain enzyme such as Insulin.
But, where the controversy between scientists stems from is due to CRISPR, before this event, only ever being used on human embryos. With scientists planning to help certain medical conditions such as Cystic Fibrosis. But, these embryos would never be replaced in the womb to grow. It was too risky ethically. Those to-be children haven't given consent to have their genetics altered, for better or for worse. Therefore, the edited embryos would have never been allowed to grow to be a living human being until more careful scientific research had happened. And then... Jiankui He used the CRISPR process so that these two babies might not get the horrible virus - HIV (See this previous post for information of these disease).
The gene that was edited was called CCR5. It's a small gene located on chromosome 3 and is used to make a protein of the same name. It's the protein that has the biggest role on the body. CCR5 is found on the surface of some white blood cells. These cells are known by scientists as T cells, macrophages and eosinophils. These are cells as well as main others which don't have CCR5 which are involved with the immune system (Source and Source 2).
Scientists have observed that this protein seems to be more expressed on cells which are turning cancerous. This is based of evidence - approximately 50% of human breast cancer cells expressing this protein (with triple negative breast cancer being more likely to express it). Therefore, it's now one of the new targets of therapy.
But, another thing that scientists have observed which is vital in this case, is that CCR5 is used by the Human Immunodeficiency Virus (HIV) to enter human cells. And... the Virus really needs a host cell to survive it (See this other blog post of mine for more information on HIV).
Scientists were never considering to edit an embryo. The idea has been thrown around. But, the goals of the US National Academies of science in 2017 was to edit a body cell (Which scientist call somatic cells) and see what happens. In this WIRED article, Sara Chan who is a biochemist and the director of the Mason Institute for Medicine, Life Science and the Law at the University of Edinburgh stated her concerns. Chan explained that we are not talking about a terminal, incurable disease anymore. HIV can be treated if help is taken swiftly enough. Therefore, Chan has some reasoning when she continued saying, to put this small marginal benefits against the large unknown risks of using gene editing is not ethical or responsible attitude.
There were two main scientific problems with the CRISPR techniques that scientists have struggled with which Jiankui He stated that he overcame. The first one is a concept within genetics called off-target effects. Off-target effects refers to the danger of editing a perfectly normal gene which lies next to the chosen one. You wouldn't want to alter a perfectly normal gene - that could have adverse effects on the individual.
The other problem is another complicated concept in genetics called mosaicism. This is where the altered gene only gets placed into some of the body cells. Meaning that there are cells that still contain the original problem gene. A reproductive scientist named Joyce Harper stated her worries (on a WIRED article) on cystic Fibrosis research. This research has used the exact same process, CRISPR. But, CRISPR might only correct 25% (a quarter) of all cells. Which means that as the person still technically has cystic fibrosis as 75% of their cells still has the cystic fibrosis gene. Science seems to have no answers on how that would affect a living person yet...
...And I wouldn't want to be the guinea pig. Would you?
The other problems with this CRISPR project was mostly ethical. Ewan Birney, also stated (in this WIRED article) that this work would almost certainly be unethical in Europe. Ewan then continued to state that this type of science needs to be regulated so society can be confident with it.
To conclude this blog post, I thought that I say that I do have some opinions to this story like I guess everyone is bound to have. I've only used facts in the main body of the post to only put forward the story. Though I can't say that I'm happy about the event. I don't want the same thing to happen to CRISPR that happened with vaccines due to the miscommunication of the main stream media on a paper that claimed autism could occur. Plus, those children have no idea that they have been genetically edited. And might not be told...
Furthermore, now that a baby has been edited many more questions have been opened. And the research about this topic has actually opened more questions then the ones that I had before.
In total 31 embryos were edited. The twins that were born counted for two of those embryos. But, there is another pregnancy occurring with an edited embryo. And... No one knows what is happening to the other 28 embryos. I just hope this doesn't affect the public trust in genetic research.
Links to Any of the Information I used
China claims to have created gene-edited babies. What happens next? (Published 27th November)
The Chinese CRISPR baby debacle takes another dark turn (Published 29th November)
Science is racing to stop another CRISPR baby from being born (Published 18th December)
The gene: CCR5
For those not of a scientific background, CRISPR is an up and coming process still in its infancy. I'll liken to as a pair of biological scissors that can cut out a chosen gene from DNA. CRISPR can even add on proteins to the DNA chain to prevent that line of genetics from being expressed. Or even force the body to constantly make that part of DNA. All parts of CRISPR is useful for different situations. At the moment, scientists are using the process to either remove undesirable mistakes from cells or promote a certain enzyme such as Insulin.
But, where the controversy between scientists stems from is due to CRISPR, before this event, only ever being used on human embryos. With scientists planning to help certain medical conditions such as Cystic Fibrosis. But, these embryos would never be replaced in the womb to grow. It was too risky ethically. Those to-be children haven't given consent to have their genetics altered, for better or for worse. Therefore, the edited embryos would have never been allowed to grow to be a living human being until more careful scientific research had happened. And then... Jiankui He used the CRISPR process so that these two babies might not get the horrible virus - HIV (See this previous post for information of these disease).
The gene that was edited was called CCR5. It's a small gene located on chromosome 3 and is used to make a protein of the same name. It's the protein that has the biggest role on the body. CCR5 is found on the surface of some white blood cells. These cells are known by scientists as T cells, macrophages and eosinophils. These are cells as well as main others which don't have CCR5 which are involved with the immune system (Source and Source 2).
Scientists have observed that this protein seems to be more expressed on cells which are turning cancerous. This is based of evidence - approximately 50% of human breast cancer cells expressing this protein (with triple negative breast cancer being more likely to express it). Therefore, it's now one of the new targets of therapy.
But, another thing that scientists have observed which is vital in this case, is that CCR5 is used by the Human Immunodeficiency Virus (HIV) to enter human cells. And... the Virus really needs a host cell to survive it (See this other blog post of mine for more information on HIV).
Scientists were never considering to edit an embryo. The idea has been thrown around. But, the goals of the US National Academies of science in 2017 was to edit a body cell (Which scientist call somatic cells) and see what happens. In this WIRED article, Sara Chan who is a biochemist and the director of the Mason Institute for Medicine, Life Science and the Law at the University of Edinburgh stated her concerns. Chan explained that we are not talking about a terminal, incurable disease anymore. HIV can be treated if help is taken swiftly enough. Therefore, Chan has some reasoning when she continued saying, to put this small marginal benefits against the large unknown risks of using gene editing is not ethical or responsible attitude.
There were two main scientific problems with the CRISPR techniques that scientists have struggled with which Jiankui He stated that he overcame. The first one is a concept within genetics called off-target effects. Off-target effects refers to the danger of editing a perfectly normal gene which lies next to the chosen one. You wouldn't want to alter a perfectly normal gene - that could have adverse effects on the individual.
The other problem is another complicated concept in genetics called mosaicism. This is where the altered gene only gets placed into some of the body cells. Meaning that there are cells that still contain the original problem gene. A reproductive scientist named Joyce Harper stated her worries (on a WIRED article) on cystic Fibrosis research. This research has used the exact same process, CRISPR. But, CRISPR might only correct 25% (a quarter) of all cells. Which means that as the person still technically has cystic fibrosis as 75% of their cells still has the cystic fibrosis gene. Science seems to have no answers on how that would affect a living person yet...
...And I wouldn't want to be the guinea pig. Would you?
The other problems with this CRISPR project was mostly ethical. Ewan Birney, also stated (in this WIRED article) that this work would almost certainly be unethical in Europe. Ewan then continued to state that this type of science needs to be regulated so society can be confident with it.
To conclude this blog post, I thought that I say that I do have some opinions to this story like I guess everyone is bound to have. I've only used facts in the main body of the post to only put forward the story. Though I can't say that I'm happy about the event. I don't want the same thing to happen to CRISPR that happened with vaccines due to the miscommunication of the main stream media on a paper that claimed autism could occur. Plus, those children have no idea that they have been genetically edited. And might not be told...
Furthermore, now that a baby has been edited many more questions have been opened. And the research about this topic has actually opened more questions then the ones that I had before.
- Where does the ethical line in lay?
- Is it OK to make a human strong or taller?
- Are people going to change the gender of a embryo to fit their desire?
- Is anyone going to way down the rules for editing humans?
In total 31 embryos were edited. The twins that were born counted for two of those embryos. But, there is another pregnancy occurring with an edited embryo. And... No one knows what is happening to the other 28 embryos. I just hope this doesn't affect the public trust in genetic research.
Links to Any of the Information I used
China claims to have created gene-edited babies. What happens next? (Published 27th November)
The Chinese CRISPR baby debacle takes another dark turn (Published 29th November)
Science is racing to stop another CRISPR baby from being born (Published 18th December)
The gene: CCR5
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