Postzygotic instability of the myotonic dystrophy p[AGC] in repeat supported by larger expansions in muscle and reduced amplifications in sperm.
We have analysed the [AGC] expansion in leucocytes, muscle and sperm from 17 individuals affected by myotonic dystrophy (DM). Skeletal muscle showed a larger repeat number than leucocytes in the same patient. A similar degree of expansion was detected in differently affected muscles of a single patient. The germline mutation (< or = 350 repeats) was expanded in somatic cells of the progeny in all patients examined. Our results provide evidence of an early postzygotic instability of the [AGC] repeat in DM.
Massari
A
A
Department of Public Health and Cell Biology, Tor Vergata University, Rome, Italy.
Gennarelli
M
M
Menegazzo
E
E
Pizzuti
A
A
Silani
V
V
Mastrogiacomo
I
I
Pagani
E
E
Angelini
C
C
Scarlato
G
G
Novelli
G
G
D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D005784:Gene Amplification; D006801:Humans; D007962:Leukocytes / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology*; D009223:Myotonic Dystrophy / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D013094:Spermatozoa / Q000502:physiology*; D015053:Zygote / Q000502:physiology*