CGG/CCG Repeat Expansions in LOC642361/NUTM2B-AS1 in Thai Patients with Oculopharyngodistal Myopathy
Issued Date
2024-07-08
Resource Type
eISSN
23767839
Scopus ID
2-s2.0-85198277512
Journal Title
Neurology: Genetics
Volume
10
Issue
4
Rights Holder(s)
SCOPUS
Bibliographic Citation
Neurology: Genetics Vol.10 No.4 (2024)
Suggested Citation
Pongpakdee S., Apiwattanakul M., Termglinchan T., Witoonpanich R., Dejthevaporn C., Lee T., Wansophonkul S., Yamanaka A., Funaguma S., Lida A., Nishino I. CGG/CCG Repeat Expansions in LOC642361/NUTM2B-AS1 in Thai Patients with Oculopharyngodistal Myopathy. Neurology: Genetics Vol.10 No.4 (2024). doi:10.1212/NXG.0000000000200170 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/99733
Title
CGG/CCG Repeat Expansions in LOC642361/NUTM2B-AS1 in Thai Patients with Oculopharyngodistal Myopathy
Corresponding Author(s)
Other Contributor(s)
Abstract
ObjectivesThis study characterizes oculopharyngodistal myopathy in 4 Thai patients from 3 families with CGG/CCG repeat expansion in LOC642361/NUTM2B-AS1.MethodsRepeat-primed PCR analyzed CGG/CCG repeat size in LOC642361/NUTM2B-AS1 in 4 Thai patients suspected of oculopharyngodistal myopathy (OPDM). Clinical records were reviewed for clinicopathologic features.ResultsAll patients exhibited strong somatic instabilities of the expanded CGG/CCG repeats, primarily manifesting as oculopharyngeal weakness. Patient 1 had mild finger extensor and intrinsic hand muscle weakness, and although patient 2 lacked limb weakness, both siblings showed electrophysiologic evidence of distal myopathy, indicative of OPDM. Patient 3, the daughter of a sibling with OPDM reported in 2004, lacked limb weakness or leukoencephalopathy on brain MRI. Patient 4, initially misdiagnosed with refractory myasthenia gravis, had generalized muscle weakness.DiscussionWhile initially characterized as oculopharyngeal myopathy with leukoencephalopathy (OPML) in a Japanese family, our study suggests a stronger association between CGG/CCG expansion in LOC642361/NUTM2B-AS1 and oculopharyngodistal myopathy (OPDM) rather than OPML. The variable presence or absence of leukoencephalopathy further supports OPDM as the predominant clinical manifestation linked to CGG/CCG expansion in LOC642361/NUTM2B-AS1.