Paternal transmission of the congenital form of myotonic dystrophy type 1: a new case and review of the literature

Am J Med Genet. 2002 Jan 22;107(3):222-6. doi: 10.1002/ajmg.10141.


Myotonic dystrophy type 1 (DM1) is an autosomal dominant trinucleotide repeat disorder that shows anticipation. The mildest manifestations of the DM gene are usually noted in individuals with the smallest repeat sizes, while congenital myotonic dystrophy (CDM) is the most common clinical outcome of the larger expansions. For many years, it was thought that CDM could only be maternally transmitted. However, in the last few years, cases of paternal transmission of CDM have been described. We report a child with the CDM phenotype and 1, 800 CTG repeats born to an asymptomatic father with 65 repeats and compare this case to the four currently in the literature. We note that polyhydramnios was present in the majority of cases and that all fathers whose status was known had small repeat sizes and/or were asymptomatic at the time of their child's birth. Although it may be unusual, the possibility of the paternal transmission of CDM should be mentioned when counseling families with DM. The men who are at highest risk may be those who have small repeats sizes and are asymptomatic.

Publication types

  • Case Reports
  • Review

MeSH terms

  • Adult
  • Blotting, Southern
  • DNA / chemistry
  • DNA / genetics
  • Family Health
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Myotonic Dystrophy / congenital
  • Myotonic Dystrophy / genetics*
  • Myotonin-Protein Kinase
  • Pedigree
  • Protein-Serine-Threonine Kinases / genetics
  • Sequence Analysis, DNA
  • Trinucleotide Repeat Expansion / genetics
  • Trinucleotide Repeats / genetics


  • DMPK protein, human
  • DNA
  • Myotonin-Protein Kinase
  • Protein-Serine-Threonine Kinases