Description

Copyright infringement not intended

Picture Courtesy: CNBCTV18

Context

Researchers at University College London (UCL) demonstrated that gene therapy (AMT-130) can slow the progression of Huntington’s disease by nearly 75% over three years. This is the first therapy proven to alter the course of the disease, not just relieve its symptoms.

What is Huntington’s Disease?

Type: Rare genetic neurodegenerative disorder.

Cause: Mutation in the Huntingtin (HTT) gene, leading to production of an abnormal huntingtin protein.

Pathology

Accumulation of toxic protein in neurons.
Progressive damage to specific brain regions (especially basal ganglia and cortex).

Symptoms

Mental disorders (depression, irritability, psychosis).
Cognitive decline (loss of memory, poor judgment, dementia).
Motor dysfunction (involuntary jerky movements, loss of coordination, difficulty in speech & swallowing).

Inheritance: Autosomal dominant (50% chance of inheritance if one parent has the mutation).

Outcome: Severe disability and premature death (usually within 15–20 years of onset).

Existing Treatments

Earlier approaches: Only symptom management using:

Antipsychotics, antidepressants (for mental symptoms).
Physiotherapy & supportive care (for motor function).

Limitation: Could not stop or slow disease progression.

New Gene Therapy (AMT-130)

Method:
- A single surgical injection into targeted brain areas.
- Uses a harmless virus (AAV5 vector) as a carrier.
- Delivers a genetic payload that silences the mutant HTT gene → reduces toxic protein synthesis.
Results:
- At high dose, disease progression slowed by 75% over 3 years.
- Some patients showed stabilization of brain volume and function.
Significance:
- First therapy to modify disease progression rather than just manage symptoms.
- Paves way for gene-based cures for other neurodegenerative diseases like Alzheimer’s, ALS, and Parkinson’s.

Source: CNBCTV18

PRACTICE QUESTION

Q. Huntington’s disease is caused by a mutation in which gene?

a) APP gene

b) HTT gene

c) SOD1 gene

d) CFTR gene

Answer: B

Explanation: Huntington’s disease is caused by a mutation in the HTT gene.

Frequently Asked Questions (FAQs)

It is a rare, fatal genetic brain disorder caused by a mutation in the HTT gene, leading to the production of a toxic protein that destroys brain cells.

It is an autosomal dominant disorder, meaning a child has a 50% chance of inheriting the mutated gene if one parent is affected.

AMT-130 is a gene therapy that uses a viral vector to deliver a payload that 'silences' the mutant HTT gene, reducing the toxic protein production.