Tzu Chi Medical Journal
Volume 20, Issue 4 , Pages 309-313, December 2008

Molecular Screening of Fragile X Syndrome in Children with Mental Retardation in Hualien

  • Jui-Hung Yen

      Affiliations

    • Institute of Human Genetics, Tzu Chi University, Hualien, Taiwan
    • ,
  • Wei-Chieh Chen

      Affiliations

    • Center of Medical Genetics, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
    • ,
  • Ching-Cherng Tzeng

      Affiliations

    • Department of Pathology, Chi Mei Medical Center, Tainan, Taiwan
    • ,
  • Jye-Siung Fang

      Affiliations

    • Institute of Human Genetics, Tzu Chi University, Hualien, Taiwan
    • Center of Medical Genetics, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
    • ,
  • Shao-Yin Chu

      Affiliations

    • Center of Medical Genetics, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
    • Department of Pediatrics, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
    • Corresponding Author InformationCorresponding author. Department of Pediatrics, Buddhist Tzu Chi General Hospital, 707, Section 3, Chung-Yang Road, Hualien, Taiwan

Received 28 March 2008; received in revised form 9 June 2008; accepted 24 June 2008.

Article Outline

Abstract 

Objective

Fragile X syndrome is the most common inherited form of X-linked mental retardation (XLMR). The aim of this study was to screen for and identify fragile X syndrome-affected individuals using DNA-based molecular approaches at a special education school for the mentally retarded in Hualien, Taiwan.

Materials and Methods

Genomic DNA extracted from 217 individuals with mental retardation, including 148 males and 69 females, was analyzed using polymerase chain reaction, DNA gel electrophoresis and Southern blot analysis. Individuals with the full mutation or premutation were determined according to the CGG repeat size in the 5′-untranslated region in the FMR1 gene on chromosome Xq27.3.

Results

A total of 217 individuals with mental retardation were screened, and three (1.38%) were identified as having fragile X full mutation. Two of the 148 males (1.35%) and one of the 69 females (1.44%) had this mutation. The incidence is very close to that in previous reports in Western Taiwan. Female carriers of fragile X syndrome were not found in this study.

Conclusion

We established a molecular screening approach and report the incidence of fragile X syndrome in a mentally retarded population in Eastern Taiwan. The molecular study and genetic counseling for other family members will continue in the future.

Keywords:  FMR1 gene , Fragile X syndrome , Mental retardation , PCR

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PII: S1016-3190(08)60056-7

doi:10.1016/S1016-3190(08)60056-7

Tzu Chi Medical Journal
Volume 20, Issue 4 , Pages 309-313, December 2008

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