What is Fragile X Syndrome (FXS)?

1 min read
What is Fragile X Syndrome (FXS)? Blog Image


To spread education and awareness among the general public about the 'Fragile X Syndrome', every year 'World Fragile X Awareness Day' is observed on July 22 across the globe.

About Fragile X Syndrome: 


  • It is an inherited genetic disease passed down from parents to children that causes intellectual and developmental disabilities.
  • It is also known as Martin-Bell syndrome.
  • It is the most common hereditary cause of mental disability in boys. It affects 1 in 4,000 boys.
  • It’s less common in girls, affecting about 1 in every 8,000. Boys usually have more severe symptoms than girls.
  • People with FXS usually experience a range of developmental and learning problems.
  • The disease is a chronic or lifelong condition. Only some people with FXS are able to live independently.
  • The peculiar quality of this disease is that if it is inherited by the father, then it will only affect the daughter, but if it is inherited by the mother, then it can affect both genders. 
  • What are the causes?
    • It is caused by a defect in the FMR1 gene located on the X chromosome.
    • The defect, or mutation, on the FMR1 gene prevents the gene from properly making a protein called the fragile X mental retardation 1 protein.
    • This protein plays a role in the functioning of the nervous system.
    • The exact function of the protein is not fully understood. A lack or shortage of this protein causes the symptoms characteristic of FXS.
  • Treatment
    • It cannot be cured. Treatment is aimed at helping people with the condition learn key language and social skills.


Q1) What is a gene?

A gene is a segment of DNA (deoxyribonucleic acid) that contains the genetic instructions for the development, functioning, and reproduction of living organisms. Genes are the basic units of heredity and play a fundamental role in determining various traits and characteristics of an organism.

Source: World Fragile X Day shines light on intellectual disability