• Scientists in India have achieved a breakthrough in treating severe haemophilia A using gene therapy. 

• Haemophilia A is a rare hereditary disorder caused by the absence of clotting Factor VIII, leading to severe and potentially fatal bleeding episodes. 

• India has the world’s second-largest haemophilia patient pool, estimated at 40,000 to 100,000 individuals. 

• Traditional treatments require frequent injections of clotting factor, which are costly and inconvenient.

• Gene therapy offers a one-time solution by introducing a therapeutic gene that enables the body to produce sufficient clotting factor.

Haemophilia A?

• Haemophilia is usually an inherited bleeding disorder in which the blood doesn’t clot properly. This can lead to spontaneous bleeding as well as bleeding following injuries or surgery. 

• The disorder primarily affects males. 

• Haemophilia is caused by a mutation or change, in one of the genes, that provides instructions for making the clotting factor proteins needed to form a blood clot.

• This change or mutation can prevent the clotting protein from working properly or to be missing altogether.

• People with haemophilia have low levels of either factor VIII (8) or factor IX (9). The severity of hemophilia that a person has is determined by the amount of factor in the blood. 

• Haemophilia A is characterised by a deficiency of the blood clotting protein known as Factor VIII that results in abnormal bleeding. 

• Hemophilia B (Christmas Disease) is caused by a lack or decrease of clotting factor IX.

• The frequency and severity of bleeding episodes depends on how much FVIII protein a person produces. 

• Severe hemophilia A is characterised by especially low levels of FVIII (less than 1 per cent in the blood) and represents about 60 per cent of all cases. 

• Severe hemophilia A may result in bleeding into vital body organs such as the kidneys and brain, which can be life-threatening if left untreated.

• Treatment for severe hemophilia A usually involves use of FVIII replacement therapy or an antibody-based medication to improve the ability of blood to clot and reduce the likelihood of bleeding.

What is gene therapy?

• Gene therapy is a medical technique aimed at modifying or manipulating the expression of genes or altering the biological properties of cells to treat or cure diseases. 

• It offers innovative solutions for conditions like cancer, genetic disorders, and infectious diseases by targeting the underlying genetic causes.

Mechanisms of gene therapy:

Gene therapy can work through several approaches:

• Replacing a faulty gene: Substituting a defective gene with a healthy version to restore normal function.

• Inactivating malfunctioning genes: Silencing genes that contribute to diseases.

• Introducing new genes: Adding new or modified genes to help combat specific diseases.

Types of Gene Therapy Products:

• Plasmid DNA: Genetically engineered circular DNA molecules used to transfer therapeutic genes into cells.

• Viral Vectors: Modified viruses, stripped of their infectious properties, act as carriers to deliver therapeutic genes to human cells.

• Bacterial Vectors: Engineered bacteria, rendered harmless, serve as vehicles to introduce therapeutic genes into tissues.

• Human Gene Editing Technology: Tools like CRISPR can disrupt harmful genes or repair genetic mutations to correct disease-causing errors.

• Patient-Derived Cellular Gene Therapy Products: Patient cells are extracted, genetically altered (often using viral vectors), and reintroduced to the patient to target diseases.

(The author is a trainer for Civil Services aspirants.)