by Dr. Aarohi Vachhrajani

Fragile X Syndrome or FXS is an inherited genetic disease which is transmitted from parents to children which is responsible for intellectual and developmental disabilities.

This syndrome can otherwise known as MARTIN-BELL SYNDROME or ESCALANTE SYNDROME.

It can majorly occur in boys rather than girls.

It is the most common cause of hereditary of mental disability in boys.



  • What Is Fragile X Syndrome????

Fragile X Syndrome


  • It is an inherited genetic disorder with intellectual disability.
  • It can be caused by interruption in a gene which is called Fragile X Mental Retardation 1 (FMR1) , This gene can be found by scientists during research.
  • The gene is responsible for brain development and growth but due to any defect in this gene the fragile x syndrome can occur.
  • The FMR1 is the form of protein.


Causes Of Fragile X Syndrome:



  • The exact cause of the syndrome is unknown as it’s an inherited genetic disorder.
  • As it’s an inherited disorder there are 50% chances of a child occurring if the mother is career.
  • If the mother is career then either the child is having the syndrome or the child is the career.
  • But if the father is having this then its chances of the gene ‘s permutation into a girl child , not a boy child.



  • To maintain the connectivity between brain cells and body tissue the protein called FMRP  is responsible.
  • In Fragile X syndrome due to gene mutation the FMRP is affected and its process of transmission also gets stopped.
  • That’s why Fragile X can occur because when FMRP is missing the signals transmitted to the brain are interrupted and misread.


Sign And Symptoms:

Sign and Symptoms


  • There are some specific signs and symptoms which proves that the child is having Fragile X syndrome.
  • They are following:
  • The symptoms are divided into 4 parts.
  1. Muscular
  2. Behavioural
  3. Developmental
  4. General body symptoms


  1. Muscular Changes:-

Flaccidity – The muscles become flaccid over time. They failed to coordinate to initiate the movement. This will directly affect the muscular movements, endurance and strength.

  1. Behavioural Changes :-

They are following :

  1. Hyperactive behavior
  2. Self hitting or self harming activities
  3. Aggressive behavior
  4. Certain repetitive movements or actions
  5. Word repetitions, speech is not clear, and can speak nonsense words repeatedly
  6. Mood changes
  7. Autistic behavior s
  8. Less eye contact
  9. Intellectual disability
  10. Poor attention span
  11. Developmental Changes :-


  1. Other General body Symptoms:-

They are following:

  1. Elongated Face
  2. Normal Body Structure
  3. Large and wide forehead
  4. Strabismus ( Eyes Crossed)
  5. Prominent and Large Ears
  6. Flat feet
  7. Soft and flashy skin
  8. Hyper extensive joints
  9. Highly Arched palates
  10. Indentation of chest
  11. Hypotonia
  12. Seizures
  13. Hand calluses
  14. Benign heart condition
  15. Large testicals

All these above mentioned were the signs and symptoms of Fragile X syndrome.


Life Span

  • The life span of the child is having Fragile X syndrome is generally normal.
  • The symptoms can’t get worse with age.
  • But as the age and height increases the body symptoms may get worse like if the child doesn’t take proper therapy then there are high chances of more muscle Flaccidity and others.





  • The diagnosis of Fragile X Syndrome is not that much easy as the symptoms aren’t shown in early age.
  • After the differential diagnosis can be done the baby is sent for a DNA test.
  • If it tests positive then it shows that the baby is having Fragile X Syndrome.
  • The other test is done which is known as Protein test, this test can reveal the level of FMR1 level.
  • By this test also one can diagnose the Fragile X Syndrome.
  • The prenatal diagnosis of Fragile X syndrome is not possible.
  • It can be diagnosed after it shows its symptoms.
  • Generally it can be diagnosed at the age of 36months for male child and 42 months for female child.
  • It’s true that genetic diseases are not curable but yes once it’s diagnosed one can maintain its level by taking proper care of the child and providing proper therapies to the child.

Fragile X Syndrome


  • The syndrome is incurable not the symptoms.
  • To Spread the awareness about the Fragile X Syndrome every year JULY MONTH is celebrated as FRAGILE X AWARENESS MONTH.
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