A shot at a perfect society
Hermon Solomon
In our bodies, genes are responsible for many things such as determining height, eye colour and sex. They are also responsible for producing a lot of necessary proteins within the body, such as enzymes – proteins that are able to speed up a reaction without changing the end products; haemoglobin – necessary for uptake of oxygen in the body; collagen – provides structure for cells, bones, organs. When a gene is damaged – a mutation – , it can lead to disastrous consequences, the most common being cancers, where the cell with the genetic alteration will grow and divide uncontrollably, leading to invasion and possible destruction of the healthy tissue surrounding it. Luckily, although a relatively new research field, genetic editing is being investigated in the hope of curing these mutations. I will be examining how gene damage may be caused, the history of genetic editing, the current state of the technology, as well as its ethical implications.
Genetic damage
Our genes are stored in DNA, a molecule of inheritance found in the nucleus of a cell. Mutations can result from DNA copying mistakes made primarily either through cell division or through exposure to chemicals called mutagen s. Within cell division, polymerase enzymes sometimes insert either too many, too few nucleotides or the wrong nucleotide into a sequence, resulting in a different strand of DNA being produced. Mutagens, on the other hand, are agents, such as radiation or a chemical substance, like tar, which causes genetic mutations. Some mutagens strip DNA nucleotides – the monomer that makes up DNA itself – of essential modifications, leading them to resemble different nucleotides and confuse the DNA replication machinery. Subsequent rounds of DNA replication then permanently incorporate such changes. 1 When the DNA code is changed, it results in a change the coding of the gene, and can result in a faulty protein being copied. In a simpler way, think of it like making tea. You need hot water, tea bags, sugar and milk (our nucleotides). Imagine the sugar is replaced with salt (a mutated nucleotide), which ruins the taste. To put it in the context of the human body, the gene that produces haemoglobin can become mutated and lead to a different structure of haemoglobin. This is known as sickle cell disease. When red blood cells sickle, they break down prematurely, which can lead to anaemia. Anaemia can cause shortness of breath, fatigue, and delayed growth and development in children. 2 Currently, the only cure for sickle cell disease is a stem cell transplant. 3 For a stem cell transplant, stem cells from a healthy donor are given through a drip into a vein. These cells then start to produce healthy red blood cells to replace the sickle cells. A stem cell transplant is an intensive treatment that carries a number of risks. Stem cell transplants usually occur in children with sickle cell disease who have severe symptoms that have not responded to other treatments, when the long-term benefits of a transplant are thought to outweigh the possible risks.
1 See Ralston 2008: 114. 2 See Ashley-Koch, Yang, Olney 2000 . 3 See NHS 2019.
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