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. 1992 May 1;89(9):4215–4217. doi: 10.1073/pnas.89.9.4215

Population genetics of the fragile-X syndrome: multiallelic model for the FMR1 locus.

N E Morton 1, J N Macpherson 1
PMCID: PMC525664  PMID: 1570349

Abstract

A model is developed to account for recent molecular observations. It postulates four alleles: normal (N), small rather stable insert (S), larger, unstable insert (Z), and large insert (L). The last-named allele causes the fragile-X phenotype, inactivation of the FMR1 locus by methylation, and mental impairment; the FMR1 locus (for fragile-X mental retardation locus 1) resides in the FRAXA region. When this model is fit to pre-molecular data, the Z allele appears to be no more frequent than L, while the S allele is polymorphic. Predictions of the model are in reasonable agreement with observation and suggest much more powerful tests of molecular data, including the Laird hypothesis that conversion of Z to L does not occur in active X chromosomes.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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