Myotonic dystrophy type 2 in Japan: ancestral origin distinct from Caucasian families.
Myotonic dystrophy type 2 (DM2) is caused by expansion of a tetranucleotide CCTG repeat in intron 1 of the ZNF9 gene on chromosome 3q21. All studied DM2 mutations have been reported in Caucasians and share an identical haplotype, suggesting a common founder. We identified a Japanese patient with DM2 and showed that the affected haplotype is distinct from the previously identified DM2 haplotype shared among Caucasians. These data strongly suggest that DM2 expansion mutations originate from separate founders in Europe and Japan and are more widely distributed than previously recognized.
Department of Neurology, National Dohoku Hospital, Asahikawa, Japan.
Tsukasa
T
Saito
Yoshinobu
Y
Amakusa
Takashi
T
Kimura
Osamu
O
Yahara
Hitoshi
H
Aizawa
Yoshio
Y
Ikeda
John W
JW
Day
Laura P W
LP
Ranum
Kinji
K
Ohno
Tohru
T
Matsuura
D017668:Age of Onset; D044466:Asian People / Q000235:genetics; D004252:DNA Mutational Analysis; D042622:DNA Repeat Expansion; D005260:Female; D018703:Founder Effect; D006239:Haplotypes; D006801:Humans; D007564:Japan; D018895:Microsatellite Repeats; D008875:Middle Aged; D009223:Myotonic Dystrophy / Q000145:classification / Q000235:genetics*; D044465:White People / Q000235:genetics