Gene Editing Treatment: World’s First Personalised Gene Therapy Treatment

Context: In the US, a baby suffering from carbamoyl phosphate synthetase 1 (CPS1) deficiency was healed with the world’s first personalised CRISPR-based gene editing treatment.

What is Carbamoyl Phosphate Synthetase 1 (CPS1) Deficiency?

• CPS1 deficiency is a rare genetic metabolic disorder that affects the urea cycle, the process by which the body removes excess nitrogen (ammonia) from the blood.
• Cause: A mutation in the CPS1 gene, which produces an enzyme needed to break down ammonia in the liver.
• Effect: Without this enzyme, ammonia builds up in the bloodstream, leading to ammonia toxicity, which can damage the brain and be life-threatening.
• Symptoms: Poor feeding, vomiting, lethargy, seizures, coma, and in severe cases, death—especially during stress, illness, or high protein intake.
• Incidence: It is extremely rare, affecting roughly 1 in 1 million

What is Gene Editing Treatment?

• It involves changing an organism’s DNA to correct genetic defects, modify how genes are expressed, or introduce new genetic material.
• It holds promise for treating difficult-to-manage conditions such as sickle cell anaemia, cystic fibrosis, and certain types of cancer.
• It targets mutated genes and changes their DNA sequence so the body can produce normal, functional proteins.
• Used especially for rare or inherited diseases where conventional drugs cannot address the root genetic cause.

What is CRISPR-Based Gene Editing Treatment?

• CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is a revolutionary gene-editing technology.
• It acts like molecular scissors: guided by a piece of RNA, CRISPR targets a specific sequence in the DNA and cuts it at a precise location.

Two key components

• Cas9, an enzyme acting as ‘molecular scissors‘ to cut DNA at specific locations.
• Guide RNA (gRNA), designed to direct Cas9 to a precise genome spot.
  • The gRNA binds to a matching DNA sequence, guiding Cas9 to make strategic cuts.
• This allows scientists to:
  • Delete a faulty gene
  • Insert a healthy gene
  • Or correct a single incorrect “letter” (nucleotide) in the DNA code

In KJ’s Case

• Doctors identified the exact faulty genetic code causing CPS1 deficiency.
• They used CRISPR to flip a single incorrect DNA letter to the correct one.
• This is customised (bespoke) gene therapy, offering potential lifelong correction of the genetic defect.

Sharing is caring!