J Korean Med Sci.  2008 Jun;23(3):470-476. 10.3346/jkms.2008.23.3.470.

Fragile X Syndrome in Korea: A Case Series and a Review of the Literature

• Yim SY
• Jeon BH
• Yang JA
• Kim HJ

• KMID: 1786887
• DOI: http://doi.org/10.3346/jkms.2008.23.3.470

Abstract

The purposes of this study were to present DNA analysis findings of our case series of fragile X syndrome (FXS) based on methylation-specific polymerase chain reaction (MS-PCR), PCR, and Southern blotting alongside developmental characteristics including psychological profiles and to review the literature on FXS in Korea. The reports of 65 children (male:female, 52:13; age, 6.12+/-4.00 yrs) referred for the diagnosis of FXS over a 26-months period were retrospectively reviewed for the identification of full mutation or premutation of fragile X mental retardation 1 (FMR1). Among the 65 children, there were 4 boys with full mutation, and one boy showed premutation of FMR1, yielding a 6.15% positive rate of FXS. All 4 children with full mutation showed significant developmental delay, cognitive dysfunction, and varying degrees of autistic behaviors. The boys with premutation showed also moderate mental retardation, severe drooling, and behavioral problems as severe as the boys with full mutation. Thirteen articles on FXS in Korea have been published since 1993, and they were reviewed. The positive rate of FXS was in the range of 0.77-8.51%, depending on the study groups and the method of diagnosis. Finally, the population-based prevalence study on FXS in Korea is required in the near future.

Keyword

Fragile X Syndrome; FMR1; Fragile X Mental Retardation Protein; Mutation; Mental Retardation

MeSH Terms

Child
Child, Preschool
Female
Fragile X Mental Retardation Protein/*genetics
Fragile X Syndrome/diagnosis/*epidemiology/*genetics
Humans
Infant
Korea/epidemiology
Male
Mutation
Prevalence

Figure

• 

  Fig. 1 The molecular diagnostic findings of fragile X syndrome.

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