Gene Editing Medicines: Are we there yet?
It was over a decade and half ago at the turn of the new millennium when scientist and journalists alike were in a frenzy about the possibilities of gene therapy and how it was going to change the world. 15 years on, the process has had time to mature and develop and today, it has shown tangible results following the hard work, research and efforts put in to it so long ago.
The BBC have reported on the story of Layla Richards, a child born with leukaemia whose parents were told she was going to die because all other treatments for her leukaemia had failed.
Thankfully the resilience of Layla, her family, her doctors and a team of specialist biotechnologists has allowed for her to be given an experimental medicine that has cured her of the cancer.
Although the experimental treatment was only used on mice, the family requested that she be given the experimental therapy to save their daughter's life.
Layla's mother, Lisa said:
"There's always got to be a first... we begged them to try something."
The experimental treatment injected into Layla contained genetically engineered immune cells which were designed to kill the cancer cells and were hardcoded to target specific areas something that wasn’t possible in the earlier stages of gene therapy.
Prof Adrian Thrasher, from Great Ormond Street Hospital, said:
"There was a lot of hype that was unrealistic at the time, the technologies were very new and it's taken 15-20 years for those technologies to mature. I think we're seeing the fruits of those early studies right now, so I think this is real."
DNA, the basics
DNA contains the instructions for our biological mechanism, how we're built, and how our bodies should operate.
Down to the tiniest detail, our DNA contains all the information needed, that if fully understood could literally allow us to be replicated. Unfortunately the same goes for our diseases, defects, health issues and even our allergies. Our DNA is the blueprint to our existence and in the case of Layla, it contained the information related to the defective genes which had left her with leukaemia.
Earlier gene therapy
In its earlier stages, gene therapy was tested on patients with weakened immune systems. Engineered genes were injected in to the patient's cells in the hope that they would replace parts of their natural damaged DNA with the engineered version, effectively curing them of having a weakened immune system.
Unfortunately this scatter gun approach meant that the engineered DNA was randomly inserted into healthy cells too, causing further disruption to the natural function of the patient's heathy cells causing additional cancers.
The latest breakthrough
But what if you were able to target just the cancerous cells, cut out the damaged DNA and replace it with an engineered version that cured the cancer? That’s exactly what Kayla received in the form of a ground breaking virus which was engineered to target only her damaged cells.
During these last 15 years some ground breaking new technologies have arrived on the scene. Zinc Fingers, Crispr and Talons are targeting technologies that effectively carry out similar tasks. They guide the engineered DNA to the cancerous cells and use what are said to be "molecular scissors" to edit the DNA.
In Kayla's case biotechnologists used white blood cells taken from a donor and Talens, to engineer a therapy by which the anti-cancer drugs given to her would no longer attack her healthy cells. An engineered virus was then introduced to Kayla's body which was coded to insert a new gene into her DNA that would attack leukaemia Cells. The results were lifesaving.
Prof Waseem Qasim, who helped treat Layla said:
"The technology is moving very fast, the ability to target very specific regions of the genome has suddenly become much more efficient.
The technology itself has got enormous potential to correct other conditions where cells are engineered and given back to patients or to provide new properties to cells that allow them to be used in a way we can only imagine at the moment."
Zinc Fingers are being experimented with to help HIV patients and Crispr have already been used in embryonic experiments. So far the tests have proved promising but Kayla's case has shown that these techniques really can work.
It seems we may have got to a turning point in cancer treatment and the future of cancer eradication doesn’t seem so far away. 15 years ago editing the very code to which we are made from would have been in the realms of science fiction, but here we are, it’s being done right now.
It's going to be interesting to see how these technologies help the thousands of patients who are misdiagnosed every year. It's clearly a game changer in the treatment of cancer and it will not be far off before we see how these technologies can be applied to a number of different illnesses.
It has been a long time coming, but undoubtedly the last 15 years of research have not been in vain. Gene therapy is here and it looks likely to transform the way that patients are treated.