Familial paroxysmal dystonic choreoathetosis: clinical findings in a large Japanese family and genetic linkage to 2q.
BACKGROUND
Paroxysmal dystonic choreoathetosis (PDC) is a rare familial movement disorder that has been mapped to chromosome 2q31-36.


OBJECTIVE
To study the first Japanese family with PDC clinically and genetically.


METHODS
We studied a large Japanese family in which at least 17 members in 6 generations have been affected by PDC. We interviewed and examined 26 family members, 8 of whom revealed choreoathetosis-like and dystonialike involuntary movement and 1 of whom revealed no involuntary movement but only muscle stiffness such as the aura of paroxysmal dystonic choreoathetosis (PDC). Genetic linkage studies of this family were carried out with polymorphic DNA markers.


RESULTS
The attacks of involuntary movement or muscle stiffness were precipitated by ovulation, menstruation, emotional stress, or caffeine or alcohol ingestion. Magnetic resonance imaging of the brain revealed no abnormalities. Clonazepam therapy was effective for reducing the attacks, and ingestion of garlic was believed by patients to be effective for softening the attacks. An affected woman with only muscle stiffness showed remission after hysterectomy for hysteromyoma. This woman also had the disease haplotype and transferred it to her typical PDC-affected daughter. Maximal pairwise logarithm of odds scores exceeding 2.00 were obtained at D2S2250, D2S1242, D2S377, D2S2148, and D2S126. The PDC gene was demonstrated by linkage analyses to be located in a 15.3-centimorgan interval lying between D2S371 and D2S339 based on pairwise and multipoint logarithm of odds scores and obligate recombination events in affected individuals.


CONCLUSIONS
Linkage of PDC to chromosome 2q32-36 was confirmed in a Japanese family. The clinical characterizations of this family with PDC include that ovulation seems also to be a precipitating factor of the attacks and that hysterectomy seems to be effective for softening the attacks. Although low-dose clonazepam treatment was most effective, garlic use was believed by affected members to be effective for softening the attacks. Furthermore, based on the results of clinical and genetic analyses, we suggest that muscle stiffness without involuntary movement may represent a forme fruste of PDC.
Matsuo
H
H
Third Department of Internal Medicine, National Defense Medical College, Saitama, Japan.
Kamakura
K
K
Saito
M
M
Okano
M
M
Nagase
T
T
Tadano
Y
Y
Kaida
K
K
Hirata
A
A
Miyamoto
N
N
Masaki
T
T
Nakamura
R
R
Motoyoshi
K
K
Tanaka
H
H
Tsuji
S
S
D001264:Athetosis / Q000235:genetics* / Q000503:physiopathology; D002819:Chorea / Q000235:genetics* / Q000503:physiopathology; D002874:Chromosome Mapping; D002889:Chromosomes, Human, Pair 2; D004421:Dystonia / Q000235:genetics* / Q000503:physiopathology; D004576:Electromyography; D005260:Female; D008040:Genetic Linkage; D005819:Genetic Markers; D006801:Humans; D007564:Japan; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology; D010375:Pedigree; D011995:Recombination, Genetic
D005819:Genetic Markers