[Distal myopathy with rimmed vacuoles(DMRV)].
Distal myopathy with rimmed vacuoles (DMRV) is an autosomal recessive muscular disorder that has been predominantly reported to occur in Japanese population. This disease is characterized clinically by weakness of the distal muscles in the lower limbs in early adulthood, most typically in the tibialis anterior muscle presenting with footdrop. Recently, the gene locus for familial vacuolar myopathy sparing quadriceps muscle with autosomal recessive inheritance (hereditary inclusion body myopathy, HIBM), which was reported to occur in Jews of Persian origin, was mapped to chromosome 9. Since DMRV and HIBM share similar clinical, genetic, and histopathological features, we performed linkage analysis on seven DMRV families. Detection of obligate recombination events as well as pairwise and multipoint linkage analyses revealed that the most likely location of the DMRV gene is in a 23.3 cM interval defined by D9S319 and D9S276 on chromosome 9, which overlap the critical region for HIBM locus. The results raise the possibility that DMRV and HIBM are allelic disease. Identification of the gene(s) for DMRV and HIBM using positional cloning strategy will lead to clarification of the genetic homogeniety for these diseases as well as the understanding in common pathways causing muscle degeneration with vacuolar formation.
Ikeuchi
T
T
Department of Neurology, Niigata University.
Tsuji
S
S
D002874:Chromosome Mapping; D002899:Chromosomes, Human, Pair 9; D005808:Genes, Recessive; D006801:Humans; D018482:Muscle, Skeletal / Q000473:pathology / Q000648:ultrastructure; D009135:Muscular Diseases / Q000235:genetics* / Q000473:pathology; D014617:Vacuoles / Q000648:ultrastructure