Meiotic stability and genotype – phenotype correlation of the trinucleotide repeat in X–linked spinal and bulbar muscular atrophy

@article{Spada1992MeioticSA,
  title={Meiotic stability and genotype – phenotype correlation of the trinucleotide repeat in X–linked spinal and bulbar muscular atrophy},
  author={Albert R. La Spada and Daniel B. Roling and Anita E. Harding and Carolyn L. Warner and Roland Spiegel and Irena Hausmanowa-Petrusewicz and Woon Chee Yee and Kenneth H. Fischbeck},
  journal={Nature Genetics},
  year={1992},
  volume={2},
  pages={301-304}
}
Expansion of the trinucleotide repeat (CAG)n in the first exon of the androgen receptor gene is associated with a rare motor neuron disorder, X–linked spinal and bulbar muscular atrophy. We have found that expanded (CAG)n alleles undergo alteration in length when transmitted from parent to offspring. Of 45 meioses examined, 12 (27%) demonstrated a change in CAG repeat number. Both expansions and contractions were observed, although their magnitude was small. There was a greater rate of… 
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