A family with PROMM not linked to the recently mapped PROMM locus DM2

Proximal myotonic myopathy is an autosomal dominantly inherited multisystem disorder, clinically similar to but genetically distinct from myotonic dys trophy (DM). A recently mapped second locus for myotonic dystrophy was thou ght to be an attractive candidate locus for PROMM, and this hypothesis was supported by reports of linkage to this locus in some PROMM families. We pr esent a large German pedigree with PROMM in which linkage to this locus cou ld be excluded, showing that PROMM is genetically heterogeneous. (C) 2000 E lsevier Science B.V. All rights reserved.