Characterization of the full fragile X syndrome mutation in fetal gametes

@article{Malter1997CharacterizationOT,
  title={Characterization of the full fragile X syndrome mutation in fetal gametes},
  author={Henry E. Malter and Jane Iber and Ralph A. Willemsen and Esther de Graaff and Jack C Tarleton and Jaakko Leisti and Stephen T. Warren and Ben A. Oostra},
  journal={Nature Genetics},
  year={1997},
  volume={15},
  pages={165-169}
}
Fragile X syndrome results from the expansion of the CGG repeat in the FMR1 gene. Expansion has been suggested to be a postzygotic event with the germline protected. From an analysis of intact ovaries of full mutation fetuses, we now show that only full expansion alleles can be detected in oocytes (but in the unmethylated state). Similarly, the testes of a 13-week full mutation fetus show no evidence of premutations while a 17-week full mutation fetus exhibits some germ cells with attributes of… 

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TLDR
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TLDR
The results strongly support the idea that fully expanded alleles are initially unstable and unmethylated in the human embryo and gain stability upon genetic or epigenetic change of the embryonic cells.

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TLDR
The hypothesis that the FMR1 CGG repeat instability is limited to very early embryogenesis in the soma is supported and the omission of ethidium bromide will facilitate the diagnosis of females with full mutation alleles is facilitated.

A unique case of reversion to normal size of a maternal premutation FMR1 allele in a normal boy

TLDR
This is the first non-mosaic case of reduction in the CGG tract of the FMR1 gene, resulting in a normal allele, and Haplotype analysis proved that the rearranged allele originated from the maternal expanded allele.

Nonrandom X inactivation and selection of fragile X full mutation in fetal fibroblasts.

TLDR
Cl cloning and serial cultivation indicate the possibility of selection depending on the activation status of the expanded X chromosome in fetal FM female fibroblasts.

Preimplantation diagnosis for fragile X syndrome based on the detection of the non‐expanded paternal and maternal CGG

TLDR
It is reported here for the first time a method for preimplantation genetic diagnosis (PGD) for fragile X syndrome based on the amplification of the CGG triplet in the normal allele.

Unexpected finding of a paternal premutation of the fragile X FMR1 gene in a female fetus of a premutation carrier mother

TLDR
Although a parental couple composed of two premutation carriers is rare, this case illustrates the importance of characterizing both parental genotypes when the results of prenatal diagnosis suggest an unusual segregation of the mutant and/or normal allele.

X Frágil

TLDR
The diagnosis of FXS has evolved from karyotype with special culture medium, to molecular techniques that are more sensitive and specific including PCR and Southern Blot, which has led to the development of investigations on pharmaceutical management or targeted treatments for FXS.

Animal model for fragile X syndrome.

TLDR
Functional studies on the FMR1 protein have shown that the protein can bind RNA and might be involved in transport of RNAs from the nucleus to the cytoplasm and a role of F MR1 protein on translation of certain mRNAs has been suggested.
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