Fragile x Syndrome
A Rare Condition
What Is Fragile X Syndrome?
Why Haven't I Heard Of It ?
FXS is actually a rare genetic condition with fewer than 200,000 U.S cases per year.
1 in 4,000 males & 1 in 8,000 females will have Fragile X Syndrome.
1 in 468 males & 1 in 151 females has the premutation.
Wait! You Never Mentioned The Symptoms!
Oops, well here are the symptoms:
-Long and Narrow Face
-A Prominent Jaw/Forehead
-Enlarged Testicles a/or Breast Development (males)
*(also common: lazy eye, scoliosis, Tremors, Single line on the palm, sunken chest)
NOTE:As the child gets older the physical characteristics of Fragile X Syndrome become more prominent, which is shown in the example below.
How Exactly Is It Caused??
Fragile x is caused by a missing protein, FMRP that is vital for brain function.
NOTE: Genes are named after they are discovered.
FMR1 actually stands for "Fragile X Syndrome Mental Retardation Gene" since it was the known cause of Fragile X Syndrome.
What is the FMR1 Gene & How Does It Relate to FXS?
The FMRI gene is usually found in the brain and in the nerves. It is used to maintain connection between cells in the brain and the nervous system. Fragile X Syndrome is caused by the absence or reduced amount of the FMR1 protein, FMRP. The most common cause of FXS is by the repetition pattern "CCG" in the DNA. This repetition leads to DNA methylation and silencing of the FMR1 gene. As a result, FMRP is not produced and that causes Fragile X syndrome.
- The picture shows the area where the FMRP protein is not present due to the silencing of the FMR1 gene
NOTE: The deletion of the FMR1 can also cause Fragile X Syndrome
How Many "CCG" repeats is needed to have FXS?
The number off "CCG" repeats dictates if a person has the premutation or the full FMR1 mutation.
Less than 45 "CCG" repeats = normal gene
45-54 "CCG" repeats = Gray zone. Individuals in the grey zone aren't known to pass on the mutation nor to develop it into the future.
52-200 "CCG" repeats=premutation. This means that later in life an individual can develop Fragile x Syndrome or it can be passed down. Most likely, as the premutated gene is passed down from generation to generation it will eventually develop into the full mutation. For example, if a mother has the permutation it is possible that when she has a child, the child will have Fragile x Syndrome.
More than 200 "CCG" repeats= full mutation
How Is Fragile X Syndrome Diagnosed?
Fragile X syndrome can be diagnosed while the child is still inside the womb by prenatal testing. Prenatal testing involves risk to the fetus as well as the mother, so it should be discussed with your health care provider. Here are the prenatal test that can be conducted:
- Amniocentesis -a sample of the amniotic fluid or fluid that surrounds the fetus within the amnion and it is tested for the FMR1 mutation.
- Chorionic Villus-A health care provider takes a sample of cells from the placenta or circular organ in the uterus that nourishes the fetus through the umbilical cord and the cells are tested for the mutation.
Parents may also notice the delayed development in their child or toddler. If a health care provider believes that their infant /child has fragile x the health care provider would refer the child to a clinical geneticist that can perform an genetic test for FXS.
NOTE: RISKS AND BENEFITS OF PRENATAL TESTNG SHOULD BE DISCUSSED WITH YOUR DOCTOR.
Is there A Cure for Fragile x Syndrome??
No, there isn't a cure for Fragile X Syndrome, but there are different treatments that may help with the symptoms
Most children with FXS can benefit from special education services that are tailored to their particular strengths and weaknesses. FXS children are eligible for free public education according to federal law, but having a medical diagnosis does not guarantee access to special education services.
Several different specialist can help manage the symptoms of fragile x syndrome.
- Occupational Therapist
- Physical Therapist
There are different medicines that are prescribed to deal with different symptoms of fragile X Syndrome, since there isn't one specific medication or cure for it.
medication name (brand)
NOTE:THIS CHART IS MEANT FOR REFERENCE ONLY AND SHOULD NOT TAKE THE PLACE OF A HEALTH CARE PROVIDER'S ADVICE. ANY QUESTIONS SHOULD BE DISCUSSED WITH YOUR HEALTH CARE PROVIDER.
Whats The Best Option For Treatment?
Can You Sum That All Up?
Fragile x syndrome is a sex liked genetic disorder that causes mild to severe intellectual disabilities and females tend to have milder symptoms. Fragile X is caused by the repetition of " CCG" repeats in the DNA. Too many repeats causes the silencing of the FMR1 and the protein it produces FMRP. FRM1 is used to maintain connection between the brain and nerve cells, if they are not produced it causes Fragile x Syndrome. Furthermore,The number of "CCG" repeats in the DNA dictates if the person has the full mutation or if they are carriers of FXS. More than 200 repeats means the person has the full mutation & 52-200 is a premutation.
The symptoms of FXS are delayed speech and hyperactive behavior. Physical characteristics include long and narrow face and prominent forehead or jaw. The diagnosis of FXS can be through prenatal testing or if a clinical geneticist runs a genetic test. Treatments include special education, therapies and medicines. The combination of these treatments is the best option for maximum results.
Where Did You Get Your Information From?
Written By: Princess
Date: March 18,2016