Publication: Cag-expansion haplotype analysis in a population with a low prevalence of huntington's disease
Issued Date
2014-01-01
Resource Type
ISSN
20055013
17386586
17386586
Other identifier(s)
2-s2.0-84892525250
Rights
Mahidol University
Rights Holder(s)
SCOPUS
Bibliographic Citation
Journal of Clinical Neurology (Korea). Vol.10, No.1 (2014), 32-36
Suggested Citation
Teeratorn Pulkes, Chutima Papsing, Sukanya Wattanapokayakit, Surakameth Mahasirimongkol Cag-expansion haplotype analysis in a population with a low prevalence of huntington's disease. Journal of Clinical Neurology (Korea). Vol.10, No.1 (2014), 32-36. doi:10.3988/jcn.2014.10.1.32 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/34718
Research Projects
Organizational Units
Authors
Journal Issue
Thesis
Title
Cag-expansion haplotype analysis in a population with a low prevalence of huntington's disease
Other Contributor(s)
Abstract
Background and PurposezzThe prevalence of Huntington's disease (HD) among East Asians is less than one-tenth of that among Caucasians. Such a low prevalence may be attributable to a lack of carriers of specific predisposing haplogroups associated with the high instability of the Huntingtin gene (HTT). The aim of this study was to evaluate the association between specific HTT haplogroups and the occurrence of HD in a Thai population. MethodszzCAG-repeat sizes and HTT haplotypes were analyzed in 18 Thai HD patients and 215 control subjects. Twenty-two tagging single-nucleotide polymorphisms (tSNPs) were genotyped. ResultszzOnly 18 patients from 15 unrelated families were identified over the last 17 years. Pathological CAG-repeat alleles ranged from 39 to 48 repeats (43.5±3.0, mean±SD), and normal alleles ranged from 9 to 24 repeats (16.49±1.74). Only two of the chromosomes studied comprised intermediate alleles. Unlike the Caucasian data, all but 1 of the 22 tSNPs were not associated with the occurrence of HD. The predisposing haplogroups for Caucasian HD (haplogroups A1 and A2) are very rare in Thai patients (<4%). Both HD and normal chromosomes are commonly haplogroups A5 and C, in contrast to the case for Chinese and Japanese patients, in whom only haplogroup C was common in HD chromosomes. The frequency of CAG-repeat sizes of haplogroup A5 and C were also similarly distributed. ConclusionszzHD chromosomes of Thai patients may arise randomly from each haplogroup, with a similar mutation rate. This rate is much lower than the CAG expansions from Caucasian HD haplogroups. These data suggest that the different mechanisms underlie CAG expansion in Thai and Caucasian patients. © 2014 Korean Neurological Association.