Gene deletions in Japanese patients with Duchenne and Becker muscular dystrophy.
Thirty-eight unrelated Japanese patients with Duchenne and Becker muscular dystrophy (DMD and BMD) have been investigated with the DMD cDNA probes. The 14-kb DMD cDNA was subdivided into 6 subclones and HindIII-digested DNAs were analyzed by Southern blotting. Out of 38 unrelated patients, 14 showed a deletion of one or several of the exon-containing HindIII fragments (36.8%). These corresponded to 50% (9/18) of BMD patients and 25% (5/20) of DMD patients, and the position and extent of deletions were mapped and proved to be more heterogeneous in DMD than in BMD. Both ends of deletions detected in probe 1-2a were common to all six BMD patients without the maintenance of reading frame of messenger RNA, and 5' ends of deletions in probe 5b-7 were also common but maintained in frame in three BMD patients. The phenotypic-specific deletion in Japanese BMD patients has existed in the 5' end of the DMD gene, although its apparently similar deletion produced a wide range of clinical courses (BMD phenotype). There was no tight correlation between clinical severity and presence or absence of deletion in DMD or BMD.
Department of Pediatrics, Gifu University, School of Medicine, Japan.
J
J
Asano
S
S
Tomatsu
K
K
Sukegawa
S
S
Yamaguchi
Y
Y
Ikedo
R
R
Minami
M
M
Iida
M
M
Nishimura
M
M
Nakagawa
M
M
Ohshiro
D000293:Adolescent; D000328:Adult; D015139:Blotting, Southern; D002648:Child; D002872:Chromosome Deletion; D006801:Humans; D007564:Japan; D008297:Male; D009136:Muscular Dystrophies / Q000235:genetics* / Q000473:pathology