Fragile X Syndrome

    Fragile X syndrome is the most common inherited form of mental impairment, according to the National Institute of Child Health and Human Development (NICHD). The syndrome does not favor any particular race, ethnic or socioeconomic group. Most people have no idea that this particular set of genetic instructions is stored within their own DNA. Because of advances in genetic research, however, health care professionals are beginning to recognize and diagnose this syndrome.

    NICHD researchers discovered the Fragile X Mental Retardation 1 gene, or FMR1, in 1991. When this individual gene “turns off,” it prevents production of a specific protein. Individuals with the full mutation of FMR1 experience symptoms because the mutated gene cannot produce enough of this protein, which is especially needed by the cells of the brain for normal functioning and development. Estimates suggest that the Fragile X mutation occurs once per 3,600 births for males and once per 4,000 births for females. Individuals who carry a permutation of the Fragile X gene rarely show symptoms but can unknowingly pass on the full mutation to their offspring. The Centers for Disease Control and Prevention estimates that one in 1,000 men and one in 250 women carry this permutation. A simple blood test can determine whether someone is a carrier or is actually affected by the syndrome.

    Symptoms

    Not every Fragile X child exhibits the same symptoms, which can make it hard to diagnose. Physical characteristics of Fragile X – including a longer-than-normal face and jaw, more noticeable ears and enlarged testicles in males – may not appear until puberty. Infants and young children may have larger heads, broad foreheads or extremely soft skin – but some may not appear any different than typical children. Most score lower than average on standardized IQ tests, indicating intellectual impairment, but all are capable of learning. More than 80 percent of boys with Fragile X have an IQ of 75 or less. (“Normal” ranges from 85 to 115). The effect on intelligence in girls, however, varies. Some may have mental impairment or a learning disability; some have normal IQs.

    Fragile X is often missed in girls, says Robin Blitz, M.D., associate director of the Arizona Child Study Center Children’s Health Center at St. Joseph’s Hospital & Medical Center.

    “Girls weren’t being tested before,” says Blitz, who recently diagnosed a 10-year-old girl with Fragile X. “Now we understand better why she has learning disabilities and anxiety and the school understands better why this young lady is having difficulty in the classroom.”

    Along with anxiety, individuals with Fragile X may exhibit attention disorders, hyperactivity and language-processing problems, which can interfere with both learning and test-taking skills.

    Individuals with Fragile X often have more capabilities than an IQ score suggests and, because these tests usually are not administered until a child reaches school age, it is important for parents to be aware of signs much earlier.

    Tracey Franks, president of the local Fragile X Chapter in Arizona, recalls that her son Nicolas, 7, diagnosed at 20 months, just wasn’t meeting developmental milestones.

    “His mode of communication was basically screaming,” she says. “We took him to Gymboree at 4 or 5 months old and he had no interest in the bubbles being blown or the parachute. “It was terrible because I was not enjoying being a mother. ‘What is wrong here?’ I thought. I didn’t realize my son wasn’t a typical child.”

    Social anxiety, tantrums, difficulty with changes in routines and a tendency to be overwhelmed by sights, sounds, and touch are other signs. Parents often feel shunned by the public when their Fragile X child looses control in a public setting. Because there is no obvious sign of physical disability, people assume the child is just not well behaved.

    Screening and treatment

    Blitz suggests screening for Fragile X if a patient receives an autism diagnosis because symptoms mimic autism. Screening also should be done if there is an occurrence of mental retardation in the extended family. She encourages parents to seek genetic counseling or an evaluation from a developmental pediatrician if they feel their child is not meeting milestones, because early intervention is critical to determine treatment. Studies show that the rate of learning among Fragile X children slows after puberty, so maximizing learning opportunity early on is critical. Begin with your child’s pediatrician, she suggests, because a primary care provider can manage and coordinate care. Any parent of a child under 3 who suspects a speech or language delay should file a referral with the Arizona Early Intervention Program so services can be provided, Blitz says.

    As an advocate for children with Fragile X, Franks says that “one of the challenges we face in Arizona is educating the medical community to look for this and diagnose it.” She urges parents not to adopt a “wait and see” attitude, but to ask for referrals if they are concerned. Soon, she hopes, the Fragile X Foundation will devise a screening program for all newborns.

    Sensory integration, neurological music therapy, part-time inclusion in a regular classroom and a companion dog named Bear have worked miracles in the life of her son, Franks says. Nicolas is starting to type what he is thinking. Educational computer games have replaced wasted hours in front of the TV. His attention span is increasing at school, he’s cutting with scissors and his receptive language is now typical for a boy his age.

    Progress at a Nicolas pace, perhaps, but progress nonetheless. You can hear the glow in Tracey’s voice as she says, “People take for granted the things that I just celebrate.”