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A complex mutable polymorphism located within the fragile X gene

Nature Genetics volume 5, pages 248–253 (1993)Cite this article

Abstract

While studying founder chromosomes in the fragile X syndrome, we have unexpectedly found linkage equilibrium to FRAXAC2, an Alu–associated microsatellite within the defective gene, FMR–1. DNA sequencing of 265 chromosomes revealed 39 alleles and a complex microsatellite of form (GT)x–C–(TA)y–(T)z. A mutation rate of 3.3% was observed but only among fragile X maternally derived meioses. Finding a second mutable locus within FMR–1 suggests that the target for tandem repeat instability may not be confined to the (CGG)nrepeat alone and raises the possibility of an FMR–1 mutation mechanism involving microsatellites.

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Authors and Affiliations

  1. Department of Human Genetics, New York State Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Rd, Staten Island, New York, 10314, USA

    Nan Zhong, Carl Dobkin & W. Ted Brown

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  1. Nan Zhong
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  2. Carl Dobkin
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  3. W. Ted Brown
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Zhong, N., Dobkin, C. & Brown, W. A complex mutable polymorphism located within the fragile X gene. Nat Genet 5, 248–253 (1993). https://doi.org/10.1038/ng1193-248

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