When my son Kyle was first being evaluated and diagnosed, one of the things he was tested for was fragile X syndrome (FXS). It’s a good idea for any child who falls on the autism spectrum or has unexplained mental retardation to be screened for this condition. Fragile X syndrome is the most common known single-gene cause of autism or autistic-like behaviors, and is typically associated with mental impairment. 2% to 6% of children diagnosed with autism are eventually diagnosed with fragile X.
What is fragile X syndrome?
Like the name indicates, fragile X syndrome is a congenital condition resulting from a chromosomal abnormality where a male’s X chromosome has not formed properly. The “X” is so fragile that it often breaks during chromosome analysis.
Boys with fragile X syndrome inherit the condition from their mothers, who are carriers of the defective chromosome. Although it is associated with mental retardation and autism, sometimes individuals with the condition have normal mental abilities. Carriers of fragile X syndrome might also have no detectable symptoms.
It has been estimated that one in every 2,000 to 3,000 births is affected by fragile X. Mothers who carry the defective chromosome have a 50% chance of passing it on to their children. The gene for fragile X has been identified as the FMR1 gene. Persons with the syndrome do not make a specific protein called FMRP (fragile X mental retardation protein). The absence of this protein is the cause of the troubling symptoms.
In children with fragile X, physical characteristics are sometimes subtle, but in adult males we see a pronounced chin and forehead, protruding ears, and genital abnormalities. Some have ataxia, or tremors and loss of balance.
Some families know the condition exists in their genetic lines and must deal with the frustrating symptoms and disabilities of fragile X. Other families may have carriers in their blood lines for generations but have no idea the condition exists until a child is born with more obvious characteristics and problems.
What can be done?
Fragile X syndrome has no cure, but there are many intervention therapies and medications which can help enormously. Children with fragile X syndrome are eligible for special education and early intervention services, according to the Individuals with Disabilities Education Improvement Act of 2004 (IDEA). These services will likely include physical therapy, occupational therapy, speech therapy, behavioral therapy, and other kinds of assistance depending on the child’s needs.
If you are concerned about your child’s mental impairments or autistic behaviors, you should insist upon a DNA blood test to rule out fragile X. Taking the test will either eliminate the possibility or start you on the road to getting answers and intervention strategies. With a diagnosis of FXS, you may want to consider genetic counseling as well.
Check out the National Fragile X Foundation website which offers information and assistance to families coping with the condition. You should reach out to other families to seek support and offer your own. Many are dealing with this challenge and still have full, satisfying, and joyous lives.
Kristyn Crow is the author of this blog. Visit her website by clicking here. Some links on this blog may have been generated by outside sources are not necessarily endorsed by Kristyn Crow.