Fragile X syndrome

Genetics

• This is caused by silencing of the fragile X mental retardation (FMR1) gene
• The mutation is dynamic and causes CGG repeat expansion
• The mutation causes the dysregulation of other genes
• There is genetic anticipation: this is usually with maternal transmission

References

1. D'Hulst C, Kooy RF. Fragile X syndrome: from molecular genetics to therapy. J Med Genet 2009; 46:577-584. 
2. Bagni C, Tassone F, Neri G, Hagerman R. Fragile X syndrome: causes, diagnosis, mechanisms, and therapeutics. J Clin Invest 2012; 122:4314-422. 
3. Marco EJ, Skuse DH. Autism-lessons from the X chromosome. SCAN 2006; 1:183–193.
4. Hagerman PJ, Stafstrom CE. Origins of epilepsy in Fragile X syndrome. Epilepsy Curr 2009; 9:108-112.
5. Berry-Kravis E, Raspa M, Loggin-Hester L, Bishop E, Holiday D, Bailey DB. Seizures in fragile X syndrome: characteristics and comorbid diagnoses. Am J Intellect Dev Disabil 2010; 115:461-472.

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