Genetically Modified Humans
Not happy with GMO’s?
Then how about genetically modified humans
Last December, humanity crossed an important line: In China, a scientist named He Jiankui announced that twins had been born in November with a gene that he had edited while they were embryos.
This seemed like earth-shaking news but the reality is that it has been done before but in a very quiet hush-hush manor. There are already genetically modified human beings living normal healthy lives in our society.
In the mid 19990’s, fertility doctors in New Jersey got an idea for how to help women have children. They suspected that some women struggle to become pregnant because of defective material in their eggs.
To rejuvenate them, the doctors drew off some of the jelly-like filling in eggs donated by healthy women and injected it into the eggs of their patients before performing in vitro sterilization.
The researchers did not ask the Food and Drug Administration for permission to try out their procedure. Only after their patients started having healthy children did they share the news that it seemed to work. Once the word got around, would-be parents streamed into clinics to try the procedure themselves.
But other people reacted with shock rather than excitement. Our cells generate fuel in miniature factories called mitochondria. And each mitochondrion carries its own small set of genes. The fertility doctors may have created children with the DNA of three people, not two.
It turned out that this was indeed the case. The doctors discovered that some of the children carried mitochondrial DNA from the donors in addition to their parents. In a 2001 report on this discovery, they called it “the first case of human germ-line genetic modification resulting in normal healthy children.” The germ line is a lineage of cells that gives rise to a new person.
The F.D.A. was not pleased. It sent the clinics letters demanding they apply to test the method as if it was a new experimental drug. Those beaurocratic hurdles were so daunting that the clinics stopped injecting eggs. By then, approximately a dozen children had been born with a mixture of DNA, There were probably many more but no one knows for sure.
The New Jersey doctors later tracked down some of these children and didn’t find anything unusual about their health as teenagers. Meanwhile, some biologists had realized that a variation on their procedure might be able to do something else: prevent diseases that are otherwise incurable.
Like the DNA in our chromosomes, the DNA in our mitochondria can mutate. Mutations cause symptoms ranging from blindness, breast and ovarian cancer to early death, and women pass them down to their children. An estimated one in 5000 people suffer from a mitochondrial disease, and for a vast majority there are no effective treatments. Scientists wondered if they could erase these diseases by swapping mitochondria.
The procedure they envisioned began with taking a patient’s chromosomes out of one of her eggs. Next they got an egg from a healthy donor and removed her chromosomes as well. Finally they inserted the patient’s chromosomes into the donor egg and fertilized it with sperm.
Tests of this so-called mitochondrial replacement therapy, carried out on mice and monkeys, offered encouraging results. But when scientists approached the United States government about trying it out on human eggs, they got shut down.
It wasn’t just the possible medical risks that worried people. Many people thought of it as a form of eugenic cloning. Two years later a provision was mysteriously slipped into a congressional budget bill that barred the FDA from even considering mitochondrial replacement therapy. So researchers went underground.
In 2016, an American fertility doctor named John Zhang announced that he had gone to Mexico to quietly carry out the procedure on a woman from Jordan with a neurological disease called Leigh syndrome. She gave birth to a boy who appeared healthy. But she and her husband had no interest in letting scientists track the health of their child. We know nothing more about the fate of this boy.
This story came back into play last December when Dr. He, an assistant professor at the Southern University of Science and Technology in Shenzhan told the world that he had made gene-edited babies by altering the DNA of human embryos with a new technology called Crispr.
He cut a small portion of DNA from a gene called CCR5. People who are missing this chunk of genetic material appear to be resistant to infections with H.I.V. Dr. He reasoned that genetically modified babies would resist the virus too.
MIT Technology Review broke the news followed by a lengthy report by the Associated Press; Dr.He with videos presented his work in a genetic editing conference in Hong Kong.
Like the New Jersey doctors before him, Dr. He was condemned for his secret recklessness. The organizers of the Hong Kong meeting issued a statement calling the birth of the twins “irresponsible”. The Chinese government called the procedure illegal and opened an investigation.
In the past when we genetically modified plants, we added DNA. We could make a wheat plant grow insulin or Coenzyme Q 10. However new strides in GMO science have allowed scientists to simple cut out bad genes rather than add new genes. It is this technology that shows great promise in cutting out the inherited genes that cause incurable illnesses such as Huntington’s disease.
Most people believe in God and that human beings came from their religion’s version of a creator. Thus they become frightened when we mere mortals start changing the very basic structure of our humanity. One could argue that when Adam and Eve bit into the apple of knowledge, this original sin empowered all humans on earth to discover good and evil for themselves and use this knowledge to advance the human race. Open-heart surgery was originally banned in the US and was pioneered by Dr.Christiaan Barnard in South Africa. Now it is a routine operation that extends our lives. Sometimes we have to put aside the thoughts of human fatality and go forward with new ideas.
Now that this method for human IVF has been developed, legislatures around the world are already adopting measures and passing laws to outlaw the procedure. As a medical person this bothers me. There may be times when editing human embryos would make medical sense. Last year, the National Academy of Sciences and the National Academy of Medicine issued detailed guidelines about what sort of cases might qualify. While they didn’t point to any particular disease, they argued that it should be considered only when no other treatment could allow parents to have a healthy child.
Fortunately, history offers us a different path. We need only look at what happened to mitochondrial replacement therapy in Britain.
When British scientists raised the idea of using the procedure on human eggs, the country conducted a serious open conversation about the pro and cons. The health department conducted a long investigation. Parliament held a public debate. And in 2015 it passed law approving the procedure.
The British government wasn’t creating a medical Wild West, where doctors were free to use the procedure whenever they wanted. Clinics had to get a license from Britain’s Human Fertilization and Embryology Authority, which would monitor the procedures and track the children throughout their lives to check for unexpected effects. The first approval was granted in February 2018 but so far the follow-up has not been reported.
Up until 1978, in vitro fertilization was also a forbidden practice. But on July 25, 1978 in Oldham, England, a baby was born as the result of Patrick Steptoe and Robert Edwards. It seems the Brits are always ahead of us.
Now this a normal procedure, even covered by provincial health insurance in Quebec. Since the discovery of Crispr, a method that allows us to cut out genes that can cause incurable diseases, we must now go forward and like open-heart surgery and IVF move into a better and heathier future in which nearly all inheritable diseases are eliminated. Imagine a world in which diseases such as autism (which involves 36 different genes), multiple sclerosis and the breast cancer genes BRCA1 and BRCA2 can be cut out of an embryo’s DNA and thus these terrible diseases are eliminated forever.
That’s the world I want my grandchildren and their children to live in. Print This Article