BioTech and Babies: What is changing in genetics today that will create humans tomorrow?
BioTech and Babies: What is changing in genetics today that will create humans tomorrow?
Human genome editing has been the subject of contentious debate within the scientific community for many years. Genome editing, also known as gene editing, involves making changes to the genetic material (DNA) of an organism to learn more about how specific genes function. Genome editing can result in changes to an organism’s physical traits, such as appearance and disease risk. Extensive research into human genome editing could provide insights as to how we can prevent life threatening diseases, such as cancer and Alzheimer’s. There are however known risks involved with human gene editing, which has raised ethical concerns as to whether the concept should be explored further. Here we look at the uses of human genome editing in healthcare, and the potential problems that may arise with advances in this technology.
Treatments involving gene editing are known as gene therapies, and these can be divided into two categories depending on the type of cells being treated. Somatic gene therapy targets the DNA of non-reproductive (somatic) cells, our normal body cells, so treatment is not passed down through generations. The process involves introducing genetic material into cells to correct a mutation or allele linked to disease. Somatic gene therapy has been used in early-stage clinical trials for the treatment of cancer and sickle cell disease. At the University of Pennsylvania, researchers genetically edited a cancer patient’s immune cells and then infused these cells back into the patient. The new data from the trial shows that the genetically edited immune cells can persist and function months after a cancer patient receives them, highlighting the potential for this technology in the treatment of diseases. In 2015, a one-year-old girl in the United Kingdom received genetically engineered immune cells to treat her aggressive childhood leukemia. At the time, the landmark treatment had only been tested on mice, and so she became the first baby girl in the world to be treated with edited immune cells.
The other form of gene therapy is known as germline therapy. This involves editing the DNA of reproductive cells (sperm and egg cells), meaning that any changes made to the DNA will be passed down through generations. For this reason, germline therapy is considered more controversial than somatic therapy, which does not alter future generations. Over recent years, gene therapy has received increased media attention due to research conducted by a scientist in China. In 2018, a woman gave birth to two genetically engineered babies, known by their pseudonyms Lulu and Nana. The aim of the experiment was to create children immune to HIV, however the experiment was widely condemned as unethical by members of the scientific community, and further investigation highlighted issues in the experimental procedure. In 2019, lead scientist He Jiankui and two of his collaborators were sentenced to three years in prison for violating medical regulations. He was released earlier this year.
His experiment has re-ignited an ongoing debate on the ethics of genome editing. Lulu and Nana’s genomes were genetically engineered using CRISPR/Cas9 technology, which involves precisely cutting DNA at a particular site identified by guide RNA. The technology was first discovered in 2012 and has since been used widely in medical research. Whilst the technology may be precise, it is not perfect and can be prone to errors. One issue to consider is that any edits made to the target gene may have an impact on the surrounding genes not intended to be edited. Such genetic modifications could have an impact on an individual’s disease risk and development. Lulu and Nana may need to be more closely monitored compared to other children, however their individual privacy and well-being will also need to be taken into account.
The impact of human genome editing extends beyond the scientific community. Whilst there is a potential for this technology to be used in health and disease management, there are concerns that genome editing would exacerbate existing socioeconomic inequalities. If for example, genome editing was used to make changes to a person’s visual appearance, or intelligence, this is something which could impact society at large. In addition to this, there are a string of ethical considerations which would need to be made. As germline therapy will impact multiple generations, is this something which can be administered if individuals cannot consent to their DNA being changed? For reasons such as these, many countries have policies in place to limit germline genome editing.
The debate surrounding human genome editing is not new and will likely continue for many years with advances in genetic research. There are already some tools available which can prevent children from inheriting serious diseases, such as IVF screening, which reduces the need for human gene editing. Gene therapy may however provide valuable insights as to how we go about treating genetic diseases which currently have no cure.