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.
Asano
J
J
Department of Pediatrics, Gifu University, School of Medicine, Japan.
Tomatsu
S
S
Sukegawa
K
K
Yamaguchi
S
S
Ikedo
Y
Y
Minami
R
R
Iida
M
M
Nishimura
M
M
Nakagawa
M
M
Ohshiro
M
M
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