Prediction of myotonic dystrophy clinical severity based on the number of intragenic [CTG]n trinucleotide repeats

Am J Med Genet. 1996 Nov 11;65(4):342-7. doi: 10.1002/(SICI)1096-8628(19961111)65:4<342::AID-AJMG18>3.0.CO;2-U.


We carried out a genotype-phenotype correlation study, based on clinical findings in 465 patients with myotonic dystrophy (DM), in order to assess [CTG] repeat number as a predictive test of disease severity. Our analysis showed that the DM subtypes defined by strict clinical criteria fall into three different classes with a log-normal distribution. This distribution is useful in predicting the probability of specific DM phenotypes based on triplet [CTG] number. This study demonstrates that measurement of triplet expansions in patients' lymphocyte DNA is highly valuable and accurate for prognostic assessment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Disease Progression
  • Female
  • Humans
  • Male
  • Myotonic Dystrophy / genetics*
  • Myotonic Dystrophy / physiopathology*
  • Predictive Value of Tests
  • Trinucleotide Repeats*