For appropriate counseling it is recommended that all members of the fragile X family under risk should be screened both by cytogenetic and molecular methods.Key Words: Fragile X syndrome, DNA analysis, Mosaicism, StB12,3 probe.
📌 3 Key Takeaways
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Objective & Hypothesis:Objective: The aim of this study was to optimize the diagnosis of the fragile X syndrome in six large families with fragile X syndrome in Turkey.Methods: Southern blot analysis was performed to identify the mutations of the FMR 1 gene localized on FRAXA locus using StB12.3 probe among 36 members (19 males, 17 females) of fragile X families and controls (8 males, 8 females) following cytogenetic analysis by fragile X induction methods.Results: Eleven males and 9 females had full mutations, while 7 males and 3 females had normal range of CGG repeats.
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Key Findings & Data:One female who was found positive by cytogenetic analysis had mosaic mutation (Y2[ll-3] with 6.0, 5.2, 2.8 kb fragment sizes).
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Conclusion & Impact:For appropriate counseling it is recommended that all members of the fragile X family under risk should be screened both by cytogenetic and molecular methods.Key Words: Fragile X syndrome, DNA analysis, Mosaicism, StB12,3 probe.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Domain Parameters
Abstract
Objective: The aim of this study was to optimize the diagnosis of the fragile X syndrome in six large families with fragile X syndrome in Turkey.Methods: Southern blot analysis was performed to identify the mutations of the FMR 1 gene localized on FRAXA locus using StB12.3 probe among 36 members (19 males, 17 females) of fragile X families and controls (8 males, 8 females) following cytogenetic analysis by fragile X induction methods.Results: Eleven males and 9 females had full mutations, while 7 males and 3 females had normal range of CGG repeats. One female who was found positive by cytogenetic analysis had mosaic mutation (Y2[ll-3] with 6.0, 5.2, 2.8 kb fragment sizes). Five females had premutations and 1 male had atypical fragment pattern.Conclusion: We suggest that, diagnosis of fragile X syndrome is not possible only by cytogenetic analysis. For appropriate counseling it is recommended that all members of the fragile X family under risk should be screened both by cytogenetic and molecular methods.Key Words: Fragile X syndrome, DNA analysis, Mosaicism, StB12,3 probe.
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Cite This Article
Keser, İ., Lüleci, G., Alkan, M. (2016). THE RESULTS OF MOLECULAR AND CYTOGENETIC ANALYSIS IN 6 FAMILIES WITH FRAGILE - X SYNDROME IN TURKEY. Marmara Medical Journal, Cilt: 13 - Sayı: 1, 7–10. https://ajindex.com/articles/688743
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