Article

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

Department of Habilitation, University Hospital of North Norway, Tromsø, Norway.
Neuromuscular Disorders (Impact Factor: 3.13). 10/2010; 21(1):41-6. DOI: 10.1016/j.nmd.2010.08.008
Source: PubMed

ABSTRACT 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.

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