Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2018 Nov 13:9:564.
doi: 10.3389/fpsyt.2018.00564. eCollection 2018.

Fragile X-Associated Neuropsychiatric Disorders (FXAND)

Affiliations
Review

Fragile X-Associated Neuropsychiatric Disorders (FXAND)

Randi J Hagerman et al. Front Psychiatry. .

Abstract

Fragile X syndrome (FXS) is caused by the full mutation (>200 CGG repeats) in the Fragile X Mental Retardation 1 (FMR1) gene. It is the most common inherited cause of intellectual disability (ID) and autism. This review focuses on neuropsychiatric disorders frequently experienced by premutation carriers with 55 to 200 CGG repeats and the pathophysiology involves elevated FMR1 mRNA levels, which is different from the absence or deficiency of fragile X mental retardation protein (FMRP) seen in FXS. Neuropsychiatric disorders are the most common problems associated with the premutation, and they affect approximately 50% of individuals with 55 to 200 CGG repeats in the FMR1 gene. Neuropsychiatric disorders in children with the premutation include anxiety, ADHD, social deficits, or autism spectrum disorders (ASD). In adults with the premutation, anxiety and depression are the most common problems, although obsessive compulsive disorder, ADHD, and substance abuse are also common. These problems are often exacerbated by chronic fatigue, chronic pain, fibromyalgia, autoimmune disorders and sleep problems, which are also associated with the premutation. Here we review the clinical studies, neuropathology and molecular underpinnings of RNA toxicity associated with the premutation. We also propose the name Fragile X-associated Neuropsychiatric Disorders (FXAND) in an effort to promote research and the use of fragile X DNA testing to enhance recognition and treatment for these disorders.

Keywords: FMR1 premutation; FXAND; FXPOI; FXTAS; fragile X-associated neuropsychiatric disorders.

PubMed Disclaimer

Similar articles

  • FMR1 Disorders.
    Hunter JE, Berry-Kravis E, Hipp H, Todd PK. Hunter JE, et al. 1998 Jun 16 [updated 2024 May 16]. In: Adam MP, Feldman J, Mirzaa GM, Pagon RA, Wallace SE, Bean LJH, Gripp KW, Amemiya A, editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993–2024. 1998 Jun 16 [updated 2024 May 16]. In: Adam MP, Feldman J, Mirzaa GM, Pagon RA, Wallace SE, Bean LJH, Gripp KW, Amemiya A, editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993–2024. PMID: 20301558 Free Books & Documents. Review.
  • Fragile X- associated Neuropsychiatric Disorders: A Case Report.
    Tan MM, Dy JB, Salcedo-Arellano MJ, Tassone F, Hagerman RJ. Tan MM, et al. Future Neurol. 2019 May;14(2):10.2217/fnl-2018-0040. doi: 10.2217/fnl-2018-0040. Epub 2019 May 24. Future Neurol. 2019. PMID: 32089651 Free PMC article.
  • Fragile X spectrum disorders.
    Lozano R, Rosero CA, Hagerman RJ. Lozano R, et al. Intractable Rare Dis Res. 2014 Nov;3(4):134-46. doi: 10.5582/irdr.2014.01022. Intractable Rare Dis Res. 2014. PMID: 25606363 Free PMC article. Review.
  • Fragile X-Associated Neuropsychiatric Disorders (FXAND) in Young Fragile X Premutation Carriers.
    Aishworiya R, Protic D, Tang SJ, Schneider A, Tassone F, Hagerman R. Aishworiya R, et al. Genes (Basel). 2022 Dec 17;13(12):2399. doi: 10.3390/genes13122399. Genes (Basel). 2022. PMID: 36553666 Free PMC article.
  • Fragile X Premutation: Medications, Therapy and Lifestyle Advice.
    Sodhi DK, Hagerman R. Sodhi DK, et al. Pharmgenomics Pers Med. 2021 Dec 29;14:1689-1699. doi: 10.2147/PGPM.S338846. eCollection 2021. Pharmgenomics Pers Med. 2021. PMID: 35002287 Free PMC article. Review.

Cited by

References

    1. Hagerman RJ, Berry-Kravis E, Hazlett HC, Bailey DB, Jr, Moine H, Kooy RF, et al. Fragile X syndrome. Nat Rev Dis Primers (2017) 3:17065 10.1038/nrdp.2017.65 - DOI - PubMed
    1. Hessl D, Wang JM, Schneider A, Koldewyn K, Le L, Iwahashi C, et al. . Decreased fragile X mental retardation protein expression underlies amygdala dysfunction in carriers of the fragile X premutation. Biol Psychiatry (2011) 70:859–65. 10.1016/j.biopsych.2011.05.033 - DOI - PMC - PubMed
    1. Pretto DI, Mendoza-Morales G, Lo J, Cao R, Hadd A, Latham GJ, et al. . CGG allele size somatic mosaicism and methylation in FMR1 premutation alleles. J Med Genet. (2014) 51:309–18. 10.1136/jmedgenet-2013-102021 - DOI - PMC - PubMed
    1. Ludwig AL, Espinal GM, Pretto DI, Jamal AL, Arque G, Tassone F, et al. . CNS expression of murine fragile X protein (FMRP) as a function of CGG-repeat size. Hum Mol Genet. (2014) 23:3228–38. 10.1093/hmg/ddu032 - DOI - PMC - PubMed
    1. Jacquemont S, Hagerman RJ, Leehey MA, Hall DA, Levine RA, Brunberg JA, et al. . Penetrance of the fragile X-associated tremor/ataxia syndrome in a premutation carrier population. JAMA (2004) 291:460–9. 10.1001/jama.291.4.460 - DOI - PubMed