What is Spinal Muscular Atrophy Type-1?

Spinal Muscular Atrophy is a neurological condition caused by a defect in the SMN1 gene.

What is Spinal Muscular Atrophy Type-1?

About Spinal Muscular Atrophy) Type-1:

  • Spinal Muscular Atrophy is a neurological condition caused by a defect in the SMN1 gene.
  • Normally, every person is born with a gene called SMN1 which produces a protein called SMN protein, in many cells in our body. 
  • This protein is essential for the normal functioning of nerve cells in the spinal cord called the ‘anterior horn cells. 
  • The anterior horn cells control the skeletal muscles essential for all our movements However, the absence of the SMN1 gene causes a reduction in the amount of SMN protein produced in anterior horn cells. 
  • Impacts of reduced SMN protein: The reduced quantity of SMN protein causes gradual death of anterior horn cells, and thus progressive weakness of muscles of limbs, trunk and breathing and swallowing muscles. 

There are broadly three types of SMA 

  • SMA Type 1: It is the most severe type of SMA. The child will never achieve independent sitting, and at best, can attain neck holding and rollover. 
  • SMA Type 2: These children will attain sitting without support, but, will not be able to walk independently. 
  • SMA Type 3: This is the milder form of SMA. The affected persons can walk independently but have difficulty walking upstairs.

How is SMA treated?

There are currently three types of medicines available for the treatment of children and adults with SMA.

  • Spinraza (Nusinersen): This is an ‘exon skipping’, with medicine injected into the spine. There is no age limit for the administration of this medicine. It works by increasing the quantity of SMN2 expression, and thus SMN protein quantity. 
  • Zolgensma: It is an artificially prepared SMN1 gene, coupled with an innocuous viral vector (AAV9) and administered as a single-dose intravenous infusion. This medicine is approved for use in children under two years of age only. 
  • Risdiplam: It is the most recently approved drug (in 2020). It is in the form of powder and the reconstituted solution is given orally, once daily, life-long.

 


Q1) What are Proteins?

Proteins are large, complex molecules that play many critical roles in the body they are made up of hundreds or thousands of smaller units called amino acids, which are attached in long chains.

Source: Baby’s treatment costs Rs 17.57 cr, father looks to central govt for help

Latest UPSC Exam 2025 Updates

Last updated on June, 2025

UPSC Notification 2025 was released on 22nd January 2025.

UPSC Prelims Result 2025 is out now for the CSE held on 25 May 2025.

UPSC Prelims Question Paper 2025 and Unofficial Prelims Answer Key 2025  are available now.

UPSC Calendar 2026 is released on 15th May, 2025.

→ The UPSC Vacancy 2025 were released 1129, out of which 979 were for UPSC CSE and remaining 150 are for UPSC IFoS.

UPSC Mains 2025 will be conducted on 22nd August 2025.

UPSC Prelims 2026 will be conducted on 24th May, 2026 & UPSC Mains 2026 will be conducted on 21st August 2026.

→ The UPSC Selection Process is of 3 stages-Prelims, Mains and Interview.

UPSC Result 2024 is released with latest UPSC Marksheet 2024. Check Now!

UPSC Toppers List 2024 is released now. Shakti Dubey is UPSC AIR 1 2024 Topper.

→ Also check Best IAS Coaching in Delhi

Vajiram Editor
Vajiram Editor
UPSC GS Course 2026
UPSC GS Course 2026
₹1,75,000
Enroll Now
GS Foundation Course 2 Yrs
GS Foundation Course 2 Yrs
₹2,45,000
Enroll Now
UPSC Prelims Test Series
UPSC Prelims Test Series
₹6000
Enroll Now
UPSC Mains Test Series
UPSC Mains Test Series
₹16000
Enroll Now
UPSC Mentorship Program
UPSC Mentorship Program
₹85000
Enroll Now
Enquire Now