DYT1 mutations amongst adult primary dystonia patients in Singapore with review of literature comparing East and West.
BACKGROUND
Dystonia is a heterogenous group of movement disorders whose clinical spectrum is very wide. At least 13 different genes and gene loci have been reported. While a 3-bp deletion in the DYT1 gene is the most frequent cause of early limb-onset, generalized dystonia, it has also been found in non-generalized forms of sporadic dystonia. An 18-bp deletion in the DYT1 gene has also been reported.


OBJECTIVE
We screened for the 3-bp and 18-bp deletions in the DYT1 gene among our sporadic, adult-onset primary dystonia patients in Singapore. We reviewed the literature to compare the frequency of DYT1 mutation between the East and the West.


METHODS
We screened 54 patients with primary dystonia (focal: n=41; segmental: n=11; multifocal: n=1; generalized: n=1) for the deletions in the DYT1 gene. A careful review of all published literature on DYT1 screening among sporadic, non-familial, non-Ashkenazi Jewish patients was done.


RESULTS
We did not detect any mutations in the exon 5 of the DYT1 gene in any of our patients. The frequency of DYT1 mutation amongst Asians (1.0%) was comparable to the West (1.56%) (p=NS).


CONCLUSIONS
DYT1 mutations are uncommon amongst adult primary dystonia patients in Singapore.
Jamora
Roland Dominic G
RD
Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore.
Tan
Eng-King
EK
Liu
Chun-Ping
CP
Kathirvel
Paramasivam
P
Burgunder
Jean-Marc
JM
Tan
Louis C S
LC
D000328:Adult; D044466:Asian People; D020821:Dystonic Disorders / Q000235:genetics*; D006801:Humans; D007194:India / Q000208:ethnology; D008296:Malaysia / Q000208:ethnology; D008875:Middle Aged; D018832:Molecular Chaperones / Q000235:genetics*; D009154:Mutation; D017384:Sequence Deletion; D012846:Singapore; D044465:White People
D018832:Molecular Chaperones; C108175:TOR1A protein, human