Gene-editing Therapy Could Be The Cure To Sickle Cell Disease

In other news, Britain's National Health Service (NHS) will provide a cutting-edge gene therapy that aims to cure sickle cell disease. The National Institute for Health and Care Excellence (NICE) confirmed the news on Friday. In 2023, Britain's MHRA medical regulator became the first in the world to approve the therapy. This therapy uses gene-editing took CRISPR.

It is a gene editing tool that uses a bacterial defense system to modify DNA in living organisms. It stands for

"clustered regularly interspaced short palindromic repeats". It was first observed in bacteria in 1987,but it was not until in 2005, when researchers discovered it was an immune system. Basically, this tool uses a guide RNA to find a specific target DNA sequence, and then a DNA-cutting enzyme to cut it.

In 2019, the first CRISPR clinical trials were conducted to treat sickle cell diseases and in 2020, this treatment was injected directed into a human patient to treat hereditary blindness.

NICE, in its statement said that the treatment would be suitable for around 50 patients per year.

What is Sickle Cell Disease?

As per John Hopkins Medicine, the sickle cell disease or SCD is an inherited blood disorder. This means that this is passed down from a parent's genes and it causes the body to make abnormal hemoglobin. The hemoglobin is the protein in the red blood cells that carries oxygen to all parts of your body. When you have SCD, your body's tissues and organs do not get enough oxygen.

Healthy red blood cells are round and flexible, allowing them to move smoothly throughout the body. In sickle cell disease (SCD), however, red blood cells become hard, sticky, and shaped like a "C" or a sickle (a curved farming tool). These misshapen cells tend to clump together, making it difficult for them to pass through small blood vessels. This blockage slows or stops the flow of oxygen-rich blood, leading to pain and potential damage to vital organs.

Unlike normal red blood cells, which live for about 120 days, sickle cells break down much sooner. This leads to a shortage of healthy red blood cells, a condition known as anemia.

The spleen, an organ that helps filter infections from the blood, also gets affected. Sickle cells can become trapped in the spleen, damaging it over time and making the body more vulnerable to infections.

How Does It Happen?

Sickle cell disease is a genetic condition, meaning it is inherited from parents. It occurs when a person receives two copies of the sickle cell gene—one from each parent. This gene affects hemoglobin, the protein in red blood cells that carries oxygen. Instead of staying round and flexible, the affected cells take on a rigid, sickle shape, leading to the complications associated with the disease.

You could be born with SCD only if 2 genes are inherited, which means it has to be 1 gene from each parent.

If you just have 1 gene, it means you are healthy, however if you partner has another genes, then your child has a greater chance of having SCD.

What are the common symptoms?

Symptoms include anemia, yellowing of the skin, eyes, and mouth, pain crisis or sickle crisis. This means when sickle cells move through blood vessels, they can get stuck and block blood flow and cause pain. This could also lead to tissue death. Other symptoms include acute chest syndrome, where these cells stick together and block oxygen flow in the vessels in the lungs; splenic sequestration, stroke, and priapism, when the cells block blood vessels in the penis, causing great pain.