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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1995 May 23;92(11):4833–4837. doi: 10.1073/pnas.92.11.4833

An n-allele model for progressive amplification in the FMR1 locus.

A Morris 1, N E Morton 1, A Collins 1, J Macpherson 1, D Nelson 1, S Sherman 1
PMCID: PMC41801  PMID: 7761409

Abstract

An n-allele model is developed for the FMR1 locus, which causes the fragile X syndrome, where n is the number of triplet repeats in the first exon. Frequencies in the general population and in index families are used to generate an n to n + delta transition matrix that predicts specific risks in satisfactory agreement with observation. However, until sequencing distinguishes between stable and unstable alleles with the same value of n, it is premature to infer whether allelic frequencies at the FMR1 locus are at equilibrium or, as some have suggested, are evolving toward higher frequencies of the pathogenic allele.

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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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