FMR1 gene on the X chromosome makes a protein
called fragile x mental retardation protein (FMRP)
FMRP – protein required for normal neural
Range of repetition of
Risk of having FXS
~6 – 44 Typical (normal)
~ 45 - 54 Intermediate
~ 55 – 200 Risk FXS (premutation/carrier)
> 200 Full mutation (FXS)
FXS depends on repetition CGG in FMR1 gene
Over sensitivity to sounds
Difficult to calm and comfort
Excessive mouthing and drooling
Playful (spinning objects, play with
exclusive toy, or part of toy)
Strabismus (inability to focus both eyes
on an object)
High blood pressure (can be treated with
Diagnosis of FXS is made through genetic testing to
determine the number of CGG repeats in FMR1
*Carrier testing: Carrier testing is used to
identify who carry a copy of gene mutation
or in two copies, causes a genetic disorder.
This type of testing is offered to individuals
who have a family history of a genetic
There is NO SPECIFIC TREATMENT for FXS
Speech-language therapists - improve their pronunciation of words
and sentences, slow down their speech, and use language more
Occupational therapists - help find ways to adjust tasks and
conditions to match a person’s needs and abilities.
Physical therapists - design activities and exercises that help build
motor control and improve posture and balance.
Behavioural therapists try to understand why someone with Fragile
X acts out, and they create ways and strategies for avoiding or
preventing these situations from occurring while also teaching
better or more positive ways to respond to situations.
However they are some symptoms that can be controlled by a
medication such as attention deficit, hyperactivity, anxiety, and
Genetic counselling maybe helpful if a
couple have family background of this
syndrome and are planning to have a baby.