Predictive testing for Huntington disease: interpretation and significance of intermediate alleles

@article{Semaka2006PredictiveTF,
  title={Predictive testing for Huntington disease: interpretation and significance of intermediate alleles},
  author={Alicia Semaka and Susan Creighton and Simon C. Warby and Michael Hayden},
  journal={Clinical Genetics},
  year={2006},
  volume={70}
}
Direct mutation analysis for Huntington disease (HD) became possible in 1993 with the identification of an expanded CAG trinucleotide repeat as the mutation underlying the disease. Expansion of CAG length beyond 35 repeats may be associated with the clinical presentation of HD. HD has never been seen in a person with a CAG size of <36 repeats. Intermediate alleles are defined as being below the affected CAG range but have the potential to expand to >35 CAG repeats within one generation. Thus… 
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