Fragile X Syndrome

Classification, Characteristics, and Classroom Tips

What is it?

Fragile X syndrome is a genetic condition which causes a range of developmental problems including learning disabilities, cognitive impairment, and can cause autism. Most males with fragile X syndrome demonstrate significant intellectual disability.

Disabilities caused can range from moderate learning disabilities to more severe intellectual disabilities. Females often have less severe intellectual disability and a milder presentation of the syndrome’s behavioral and physical features.

Fragile X syndrome occurs in about 1 in 4,000 males and 1 in 8,000 females.

What causes it?

Fragile X syndrome is caused by a lengthening of the X chromosome known as a gene mutation. Normally the X chromosome contains between 6 and 50 repeats of the CGG triplet repeat which is inside the gene FMR1, which provides instructions for making a protein called fragile X mental retardation 1 protein, or FMRP. In carriers, this sequence contains between fifty and 200 repeats.

Fragile X syndrome is caused when the sequence lengthens to over 200 repeats. The repeats shuts off production of the FMRP, which is vital for normal brain development

Fragile X syndrome is inherited in an X-linked dominant pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. Boys and girls can both be affected, but because boys have only one X chromosome, a single fragile X is likely to affect them more severely. You can have fragile X syndrome even if your parents do not have it, as they may be unaffected carriers.

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Characteristics of Fragile X

Developmental Symptoms

  • Delay in crawling, walking, or twisting
  • Hand clapping or hand biting
  • Hyperactive or impulsive behavior
  • Intellectual disability
  • Speech and language delay
  • Tendency to avoid eye contact

Fragile X Syndrome and Education

Typical strengths and idiosyncrasies of the fragile X student:

Visual memory - related to spatial/placement of objects, order, or format
  • Simultaneous learners - the "gestalt" is most easily remembered
  • Facts are most efficiently retrieved through contextual cues or associations
  • Incidentally acquired knowledge - demonstration of knowledge, which has never been formally taught
  • Socially motivated - enjoys social interaction with peers and adults
  • Imitates speech and voice intonation patterns
  • Understands concepts when illustrated during the time of the presentation - less intimated when asked to give a visual response or to formulate one through pictures
  • Acutely aware of environmental conditions such as noise, changes in physical appearance, visual properties (hyper vigilance)
  • Excellent sense of humor - engages peers or adults in humor, accurately utilizes humor in an appropriate context
  • Often very receptive to helping or working cooperatively


Developing an IEP For the Individual with Fragile X

Typical Needs:

1) Increase ability to tolerate change in routine/environment

2) Sensory integrative therapy

3) Increase receptive and expressive language levels

4) Increase frequency of spontaneously initiated verbal interactions

5) Increase intelligibility of speech

6) Increase independent toileting

7) Increase tolerance for a variety of foods

8) Increase attending behaviors: at task, sitting, and delayed reinforcement

9) One-to-one instruction for novel tasks

10) Inclusion with typical age-appropriate peers when appropriate

11) Decreased mouthing, hand biting or finger/clothing chewing

12) Increase competency in play skills

13) Increase fine motor skills

14) Decrease tantruming while providing ways to calm self

15) Decrease ritualistic and obsessive behaviors

16) Decrease person/environment specific behaviors

17) Increase tolerance to touch or a variety of textures

18) Decrease anxiety

19) Initiate calming of self

*These needs have been taken from a variety of IEP's written for individuals with fragile X.

Programming Goals for an Individual Education Plan:

1. Sensory integrative therapy to:

  • Decrease hypersensitivity to tactile, visual, olfactory, gustatory, and auditory stimuli
  • Increase tolerance of change in routine and environment
  • Decrease mouthing, hand biting, chewing on clothing
  • Decrease ritualistic behaviors
  • Improve gross and fine motor skills
  • Improve motor planning skills

2. Speech/language therapy to:

  • Increase receptive and expressive language levels
  • Increase mean length of utterance
  • Increase problem-solving skills
  • Increase play skill competency
  • Increase use of a variety of speech acts
  • Decrease verbal perseverations
  • Increase frequency of spontaneously initiated verbalizations
  • Decrease fast rate and oral and speech dyspraxia

3. Combined sensory integration and speech/language therapy to apply basic sensorimotor strategies into developing speech, language, and pragmatic skills.

4. Educational intervention to:

  • Increase attending behaviors in all situations
  • Increase independent toileting
  • Decrease person/environment specific behaviors
  • Decrease tantruming
  • Increase play skill competencies
  • Increase mainstreaming with normal age-appropriate peers

Taken from Fragile X syndrome; Diagnosis, Treatment, and Research. Edited by Randi Jenssen Hagerman, M.D. and Amy Cronister Silverman, M.S.

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