Journal of Rafsanjan University of Medical Sciences

  Evaluation of Fragile X Syndrome in Patients with Moderate Mental Retardation in Rafsanjan City

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 Mirzaei MSPH [1] , GR. Asadi Karam PhD [2] , M. Mahmoodi PhD [3] , Hajizadeh MSc [4] ¸ M. Musavi MSPH [5] , AR. Sayadi MSc [6] , S.H. Hosseini�MSc⁶

  Background and Objective: Fragile X syndrome (FXS) is the most common cause of inherited mental retardation. Patients are identified with different levels of mental disabilities, elongated ears, prominent foreheads and chins, enlarged testes, large skull and obesity. This syndrom is generally associated with a break on X chromosome (Xq27.3), which can be observed in cultured chromosomes in specific culture media at metaphase stage. Prevalence rates of FXS in different ethnic groups have been estimated to be about one per 1500 in males and one per 2500 in females. The aim of this study was to determine FXS prevalence in moderate mental retarded students of Zohreh Shamsaei school in Rafsangan city.

  Materials and Methods: Fifty two students with moderate mental retardation (IQ=55-75) who were clinically suspicious to have FXS were screened for fragile X chromosome by using cytogenetic methods. Blood samples were collected and cultured in specific culture media. G-Banding method was used for karyotyping.

  Results: Patients consisted of 37 males (71.2%) and 15 females (28.8%) with mean age of 12.7 years (ranged 7-17 years)^�and mean IQ 65.3 (ranged 55-74). 8.1% of male students and 6.6% of female students were found to have fragile X site at Xq27.3 (in total 7.7%). The frequencies of fragile X-positive cells in males and females were 8-52% and 12-27%, respectively.

  Conclusion: The frequency of fragile X positive cases found in this study is equal to that is reported by other investigators who studied the frequency of fragile X syndrome in preselected patients.

  Key words: Fragile X syndrome, Mental Retardation, Karyotype

  [1] -Academic Member, Dept. of Biochemistry Biophysics, Genetics and Tatrition , University of Medical of Sciences,
Rafsanjan

  Corresponding Author, Tel:(0391) 5225400, Fax: (0391) 5225209, E - mail: mirzaee-mr@yahoo.com

  [2] - Associated Professor of Medical Biochemistry, University of Medical of Sciences, Rafsanjan

  [3] - Associated Professor of Clinical Biochemistry, University of Medical of Sciences, Rafsanjan

  [4] - Academic Member, Dept. of Medical Biochemistry, University of Medical of Sciences, Rafsanjan

  [5] - Academic Member, Dept.of Microbiology, University of Medical of Sciences, Rafsanjan

  [6] - Academic Member, Dept.of Basic Sciences ,Neursing School, University of Medical of Sciences, Rafsanjan