Fragile X

What is Fragile X?

Fragile X is a genetic condition caused by a change in the FMR1 gene. When looked at, a part of the X chromosome appears "fragile". It is the most common cause of inherited mental impairment. It can affect people in ways ranging from learning disabilities to even more severe psychological disabilities.

The History

1910 Thomas Hunt Morgan demonstrates that when a gene is located on the X chromosome of the fruit fly, the characteristic appears more frequently in males than in females.

Hemophilia exhibits a similar pattern of X-linked inheritance.

1943 Martin and Bell show that a particular form of mental retardation is X-linked.

1969 Herbert Lubs finds visual proof of the linkage of mental retardation and the X chromosome.

Symptoms

Physical Features

Behavioral and Social Characteristics

Large /protruding ears Recurrent otitis media in childhood Soft skin Flexible joints ( particularly fingers, wrists, elbows) Low muscle tone Flat feet Long face Large testicles (males) Seizure disorder

Speech and language delay Motor delay (late crawling, walking, toileting) Tactile defensiveness and sensory overload (high sensitivity to various fabrics/clothing, loud noises, crowds, food textures & tastes, etc.) Hand-flapping, hand-biting Impulsive Poor eye contact/gaze aversion Autism spectrum disorders ADHD (attention deficit/hyperactive disorder) Mental retardation, cognitive impairment or intellectual disability

Causes

The Fragile X gene is passed down from either parent to either child. It's sex-linked recessive. The FMR1 gene normally produces a protein needed for your brain to grow correctly, but the defect causes for little or none at all to be produced.

Diagnosis and Treatments

There is a blood test, created in 1992, that can detect both carriers and victims. There is no current cure for Fragile X. There are educational programs and training to help people affected by FXS.

Preventions and Precautions?

Hopeful parents may try genetic counseling if there is a history of the disorder in the family to see what the chances of having a child affected by FXS are.

Research

Within the last 6 years there have been over 30 different research studies conducted for FXS. The studies included things like ovarian research, social skills and gene expression.

Support Groups

National Fragile X Foundation -- National Fragile X Foundation

Want More?

Works Cited

"Fragile X Syndrome - Symptoms, Diagnosis, Treatment of Fragile X Syndrome - NY Times Health Information." Health News - The New York Times. Ed. Diana Chambers. 08 Nov. 2009. Web. 24 Mar. 2011. .


"Current Reseach Studies - National Fragile X Foundation." The National Fragile X Foundation - Fragile X Syndrome. Web. 24 Mar. 2011.


"YouTube - Understanding Fragile X Syndrome." YouTube - Broadcast Yourself. Feb. 2005. Web. 24 Mar. 2011. .

Preguntas

1. What are some symptoms of Fragile X?
2. What kind of research is being conducted?
3. How is it tested?
4. It is caused by a change in which gene?
5. What does this gene do?