Fragile X syndrome: Learning what families need, one person at a time.

Family sitting on a red bench

Fragile X syndrome (FXS) is a rare genetic disorder that has a major effect on a person’s life. It is the most common cause of inherited intellectual disability, yet there are still many unanswered questions about its effect on the day-to-day lives of people living with FXS and their families. Learn what CDC and partners are doing to learn more about FXS, one case at a time.

Fragile X syndrome: Unanswered questions

The signs and symptoms of FXS and its effects can vary greatly from person to person. Children and adults with FXS may have problems with memory, abstract thinking, problem solving, and planning. Social and behavioral problems, difficulty with learning, developmental delays, and autism spectrum disorder are common, as are anxiety and depression. People with FXS may also be at higher risk for some health conditions, including ear infections, difficulty sleeping, seizures, and gastrointestinal problems such as diarrhea and gastric reflux. FXS affects both males and females; however, females often have milder symptoms than males. Males with FXS are usually diagnosed with some form of intellectual or developmental disability.

Having a child with FXS can mean many challenges for families. Some parents spend years taking their child to different doctors before getting a diagnosis of FXS. Others struggle with the behavioral and communication challenges that come with FXS. Children with FXS often take longer to reach developmental milestones and struggle to master the skills they need to become independent and self-sufficient. This may mean they require a lot of extra care and support. These are just some of the examples of the broad impact of FXS on families.

During the past several decades, scientists have made advancements in understanding the genetics of FXS. However, we are just beginning to understand how this complex condition affects people and their families. To help these families, we need to learn more about

  • Other conditions that commonly occur with FXS
  • Effects on the day-to-day lives of people living with FXS and their families
  • Short-term and long-term outcomes
  • Types of intervention and support that are most effective for each individual and their family.

FORWARD: A CDC-funded research study to learn about the lives of people with FXS

FORWARD (Fragile X Online Registry with Accessible Research Database) is a CDC-funded research study designed to learn more about FXS. FORWARD is a collaboration between CDC, the Fragile X Clinical Research Consortium (a group of FXS specialty clinics located throughout the United States), and the National Fragile X Foundation. The goal of the FORWARD study is to better describe how people with FXS develop and change over time. This information can help guide efforts to improve the lives of children and adolescents with FXS and their families.

FORWARD has gathered data from more than 1,800 people with FXS. Between 2012 and 2021, FORWARD invited clinic patients with FXS and their families to provide information on topics such as medical history, medication use, behaviors, and educational services. This information is a valuable resource for learning more about FXS and is stored in a research database.

More than 20 scientific reports using the FORWARD database have been published to date. One published report describes how the timing and success of toilet training in children with FXS can vary depending on a child’s individual characteristics. Other recent reports have described medication use to treat symptoms including anxiety and attention problems and the prevalence of seizures in people with FXS. These results can help health professionals and families understand what to expect after an FXS diagnosis.

A new phase of the FORWARD study, called FORWARD-MARCH (Multiple Assessments for Research Characterization), began in the fall of 2022. Using information from families and health professionals, FORWARD-MARCH will collect detailed data on cognition (thinking), behavior, and daily functioning. Between 2022 and 2026, researchers will invite about 600 children and young adults with FXS and their families to participate in FORWARD-MARCH, including many participants from the FORWARD study. What we learn from FORWARD-MARCH can help individuals with FXS receive appropriate and well-timed services. Information from FORWARD-MARCH may also help researchers design improved studies of new medical or behavioral treatments for people with FXS.

CDC’s work on fragile X syndrome

In addition to funding the FORWARD study, CDC activities include

Collaboration with the American Academy of Pediatrics on two projects:

  • The development and distribution of educational materials to healthcare professionals and families. These materials are designed to raise awareness of FXS and encourage early diagnosis so that people with FXS can receive appropriate care and services. Learn more.
  • The development and production of a webinar, “Continuing Medical Education and Identification, Management, Caring for Children and Adolescents with Fragile X Syndrome.” Clinicians interested in this education can access the recorded module and earn free CME and MOC credit. Register here.
More Information
  1. Choo, T. H., Xu, Q., Budimirovic, D. B., Lozano, R., Esler, A. N., Frye, R. E., Andrews, H., Velinov, M. (2022) Height and Body Mass Index in Fragile X Syndrome: A Longitudinal Assessment. Obesity (Silver Spring), 30: 743– 750.
  2. Berry-Kravis, E., Filipink, R. A., Frye, R. E., Golla, S., Morris, S. M., Andrews, H., Choo, T-H., Kaufmann, W. E., & the FORWARD Consortium (2021). Seizures in fragile X syndrome: Associations and longitudinal analysis of a large clinic-based cohort. Frontiers of Pediatrics. 9:736255.
  3. Dominick, K. C., Andrews, H. F., Kaufmann, W. E., Berry-Kravis, E., & Erickson, C. A. (2021). Psychotropic drug treatment patterns in persons with fragile X syndrome. Journal of Child and Adolescent Psychopharmacology. 31:659-69.
  4. Budimirovic, D. B., Protic, D. D., Delahunty, C. M., Andrews, H. F., Choo, T. H., Xu, Q., Berry-Kravis, E., Kaufmann, W. E., & the FORWARD Consortium (2021). Sleep problems in fragile X syndrome: Cross-sectional analysis of a large clinic-based cohort. American Journal of Medical Genetics. Epub ahead of print
  5. Meng, L., Kaufmann, W. E., Frye, R. E., Ong, K., Kaminski, J. W., Velinov, M., Berry-Kravis, E. (2021). The association between mosaicism type and cognitive and behavioral functioning among males with fragile X syndrome. American Journal of Medical Genetics. Epub ahead of print
  6. Ethridge, L., Thaliath, A., Kraff, J., Nijhawan, K., & Berry-Kravis, E. (2020). Development of neural response to novel sounds in fragile X syndrome: Potential biomarkers. American Journal on Intellectual and Developmental Disabilities125(6), 449–464.
  7. Aman, M. G., Norris, M., Kaat, A. J., Andrews, H., Choo, T. H., Chen, C., Wheeler, A., Bann, C., & Erickson, C. (2020). Factor structure of the aberrant behavior checklist in individuals with fragile x syndrome: Clarifications and future guidance. Journal of Child and Adolescent Psychopharmacology30(8), 512–521.
  8. Cordeiro, L., Villagomez, A., Swain, D., Deklotz, S., & Tartaglia, N. (2020). Adaptive skills in FXS: A review of the literature and evaluation of the PEDI-Computer Adaptive Test (PEDI-CAT) to measure adaptive skills. Brain Sciences10(6), 351.
  9. Cordeiro, L., Braden, M., Coan, E., Welnick, N., Tanda, T., & Tartaglia, N. (2020). Evaluating social interactions using the Autism Screening Instrument for Education Planning-3rd edition (ASIEP-3): Interaction assessment in children and adults with fragile X syndrome. Brain Sciences10(4), 248.
  10. Reisinger, D. L., Shaffer, R. C., Tartaglia, N., Berry-Kravis, E., Erickson, C. A. (2020). Delineating repetitive behavior profiles across the lifespan in fragile X syndrome. Brain Sciences, 10(4):239.
  11. Hoffmann, A., Wang, A., Berger, N., Cordeiro, L., Shaffer, R., Tartaglia, N., Erickson, C., & Berry-Kravis, E. (2020). Language across the lifespan in fragile X syndrome: Characteristics and considerations for assessment. Brain Sciences10(4), 212.
  12. Coffman, M. C., Shaffer, R. C., Schmitt, L. M., Dominick, K. C., Pedapati, E., Wang, A., Berry-Kravis, E., Tartaglia, N., & Erickson, C. A. (2020). Examination of correlates to health-related quality of life in individuals with fragile X syndrome. Brain Sciences10(4), 213.
  13. Kidd, S. A., Berry-Kravis, E., Choo, T. H., Chen, C., Esler, A., Hoffmann, A., Andrews, H. F., & Kaufmann, W. E. (2020). Improving the diagnosis of autism spectrum disorder in fragile X syndrome by adapting the Social Communication Questionnaire and the Social Responsiveness Scale-2. Journal of Autism and Developmental Disorders50(9), 3276–3295.
  14. Berry-Kravis, E., Kidd, S. A., Lachiewicz, A. M., Choo, T. H., Tartaglia, N., Talapatra, D., Aguirre-Kolb, C., Andrews, H., & Riley, K. (2019). Toilet training in fragile X syndrome. Journal of Developmental and Behavioral Pediatrics40(9), 751–761.
  15. Gilbertson, K. E., Jackson, H. L., Dziuban, E. J., Sherman, S. L., Berry-Kravis, E. M., Erickson, C. A., & Valdez, R. (2019). Preventive care services and health behaviors in children with fragile X syndrome. Disability and Health Journal12(4), 564–573.
  16. Eckert, E. M., Dominick, K. C., Pedapati, E. V., Wink, L. K., Shaffer, R. C., Andrews, H., Choo, T. H., Chen, C., Kaufmann, W. E., Tartaglia, N., Berry-Kravis, E. M., & Erickson, C. A. (2019). Pharmacologic interventions for irritability, aggression, agitation and self-injurious behavior in fragile X syndrome: An initial cross-sectional analysis. Journal of Autism and Developmental Disorders49(11), 4595–4602.
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