Unique PABP2 mutations in "Cajuns" suggest multiple founders of oculopharyngeal muscular dystrophy in populations with French ancestry.
Oculopharyngeal muscular dystrophy (OPMD) is an adult-onset autosomal dominant myopathy found world-wide, but with the highest incidence in French-Canadians. Short GCG expansions in the poly(A) binding protein 2 (PABP2) gene were identified recently as the molecular basis for OPMD in French-Canadians. All French-Canadian cases of OPMD have been traced to a single founder couple [Bouchard, 1997: Neuromuscul Disord 7(Suppl):S5-S11]. Cultural links between French-Canadians and Cajuns suggest that this same founder couple may have transmitted the OPMD mutation to Cajuns as well. To determine if OPMD patients from Louisiana share a founder effect with French-Canadian families, we collected blood samples and muscle biopsies from several Cajuns with OPMD for mutation and linkage studies. We found a unique 'GCA GCG GCG' insertion mutation in Cajuns. Consistent with these sequence data, we identified a disease haplotype in our Cajun families that is different from the ancestral haplotype defined in French-Canadians. These data prove that different founders introduced the PABP2 mutation to Cajuns and French-Canadians and lend support to emerging genealogical data suggesting that French-Canadians and Cajuns represent distinct immigrant groups from France.
Scacheri
P C
PC
Department of Molecular Genetics and Biochemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
Garcia
C
C
Hébert
R
R
Hoffman
E P
EP
D001483:Base Sequence; D002170:Canada / Q000208:ethnology; D004268:DNA-Binding Proteins / Q000235:genetics*; D005006:Ethnicity / Q000235:genetics*; D005260:Female; D005602:France / Q000208:ethnology; D006801:Humans; D008145:Louisiana; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics*; D009136:Muscular Dystrophies / Q000235:genetics*; D010375:Pedigree; D039103:Poly(A)-Binding Protein II
D004268:DNA-Binding Proteins; D039103:Poly(A)-Binding Protein II