Abstract
Oculopharyngeal muscular dystrophy (OPMD) is an autosomal dominant late-onset neuromuscular degenerative disease characterized by ptosis, dysphagia, and proximal muscle weakness. The genetic basis has been identified as an abnormal (GCN) expansion encoding the polyalanine tract in exon 1 of the polyadenylate-binding protein nuclear 1 gene (PABPN1). OPMD is worldwide distributed, but has rarely been reported in East Asians. In this study, we summarized the clinical and genetic characteristics of 34 individuals from 13 unrelated families in Chinese population. In our cohort, the mean age at onset was 47.2 years. Dysphagia, rather than ptosis, was the most common initial symptom. Genetically, we identified seven genotypes in our patients, including one compound heterozygote of (GCN)11/(GCN)12. The genetic heterogeneity implies that there is no single founder effect in Chinese population, and our data also support that the (GCN)11 polymorphism may have a disease-modifying effect. Additionally, the clinical features showed homogeneity within families, which suggests that other genetic factors apart from the already known genotype also play a role in modifying the phenotype.
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Acknowledgments
We thank the patients and their families for their participation. We thank Alyssa Nylander (Neurology Department, Yale School of Medicine, Yale University, CT, USA) for careful review of the grammar in our manuscript. This work was supported by China Postdoctoral Science Foundation and Doctoral Fund of Ministry of Education of China.
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The authors declare that they have no conflict of interest.
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Samples from patients were obtained in accordance with the Helsinki Declaration of 1964, as revised in 2000, and with the appropriate signed informed consent. The study was approved by the Ethical Committee of Shandong University and Peking University.
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Jingli Shan and Bin Chen have contributed equally to this work.
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Shan, J., Chen, B., Lin, P. et al. Oculopharyngeal Muscular Dystrophy: Phenotypic and Genotypic Studies in a Chinese Population. Neuromol Med 16, 782–786 (2014). https://doi.org/10.1007/s12017-014-8327-5
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DOI: https://doi.org/10.1007/s12017-014-8327-5