Prevalence, mutation spectrum and phenotypic variability in Norwegian patients with Limb Girdle Muscular Dystrophy 2I

Neuromuscul Disord. 2011 Jan;21(1):41-6. doi: 10.1016/j.nmd.2010.08.008. Epub 2010 Oct 18.


Mutations in the FKRP (Fukutin Related Protein) gene produce a range of phenotypes including Limb Girdle Muscular Dystrophy Type 2I (LGMD2I). In order to investigate the prevalence, the mutation spectrum and possible genotype-phenotype correlation, we studied a cohort of Norwegian patients with LGMD2I, ascertained in a 4-year period. In this retrospective study of genetically tested patients, we identified 88 patients from 69 families, who were either homozygous or compound heterozygous for FKRP mutations. This gives a minimum prevalence of 1/54,000 and a corresponding carrier frequency of 1/116 in the Norwegian population. Seven different FKRP mutations, including three novel changes, were detected. Seventy-six patients were homozygous for the common c.826C>A mutation. These patients had later disease onset than patients who were compound heterozygous - 14.0 vs. 6.1 years. We detected substantial variability in disease severity among homozygous patients.

MeSH terms

  • Adult
  • Age of Onset
  • Family Health
  • Female
  • Genetic Association Studies
  • Humans
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Muscular Dystrophies, Limb-Girdle* / epidemiology
  • Muscular Dystrophies, Limb-Girdle* / genetics
  • Muscular Dystrophies, Limb-Girdle* / physiopathology
  • Mutation / genetics*
  • Norway / epidemiology
  • Pentosyltransferases
  • Phenotype*
  • Prevalence
  • Proteins / genetics*
  • Retrospective Studies
  • Young Adult


  • Proteins
  • FKRP protein, human
  • Pentosyltransferases