Fragile X syndrome is the most common known genetic cause of autism, among other conditions. This genetic anomaly is found in both males and females.

Fragile X syndrome is an inherited genetic condition that has been linked to a number of disorders. The affected X chromosome does not produce a needed protein, called fragile x mental retardation protein or FMRP. It is most severe in males, because they have only one X chromosome. In females, the unaffected X chromosome makes the protein, and lessens the impairments caused by fragile X.

Mental Impairment

One of the most prevalent effects of fragile X syndrome is mental impairment. The National Fragile X Foundation website states, “This impairment can range from learning disabilities to more severe cognitive or intellectual disabilities. (Sometimes referred to as mental retardation.)” It is believed that fragile X syndrome is responsible for two to three percent of all undiagnosed cases of mental impairment.

Language Delay

Language delay is common in males with fragile X syndrome. According to the National Fragile X Foundation, there are too many variations within the Fragile X male population to describe specific language characteristics. However, most learn to speak with the aid of therapy and the use of picture systems such as PECS or sign language. Physical problems, like repeated ear infections or sensory motor problems may exacerbate the problem. Mental impairment or attention deficit disorder hava also been cited as components of speech delay in these individuals.

Fragile X females do not normally suffer language delay. However, their conversational skills, known as pragmatics, may be a weakness due to other fragile X traits. These traits include poor executive (planning) skills, shyness and anxiety.

Autism

About one-third of all known fragile X individuals have been diagnosed with autism or an autism spectrum disorder. This makes up approximately two to six percent of all autism cases. Fragile X mutations cause autism because FMRP, which is not produced in quantity or not produced at all by the affected X chromosome, is related to many developmental functions. These findings do not imply that those with autism caused by fragile X cannot benefit from treatment. Currently, work is being done to treat the genetic anomaly on a genetic level, according to Fragile X Syndrome: A Genetic Model for Autism with Targeted Treatments, an article offered by the National Fragile X Foundation.

_{A simple DNA test can diagnose Fragile X Syndrome - source}

Physical Characteristics

The physical characteristics identified with fragile X individuals are mostly found in males. However, females may have these in a lesser form:

• elongated face
• long ears
• large head circumference
• enlarged testes (after puberty)
• connective tissue problems
• high arched palate (females)

As research into the human genetic make-up continues, scientists will unlock more information about this syndrome and treatments for those who have been diagnosed. In the interim, if you have suspicions your child may be affected, a simple DNA test can be performed. It is urged that all autistic or autism spectrum individuals be tested for fragile X syndrome.

Source:
The National Fragile X Foundation: https://fragilex.org/learn/