Heterozygous Variants in KCNJ10 Cause Paroxysmal Kinesigenic Dyskinesia Via Haploinsufficiency.

Autor: Li YL; Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian, China., Lin J; Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian, China., Huang X; Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian, China., Zeng RH; Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian, China., Zhang G; Department of Rehabilitation Medicine, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China., Xu JN; Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian, China., Lin KJ; Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian, China., Chen XS; Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian, China., He MF; Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China., Qiao JD; Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China., Cheng X; Lingang Laboratory, Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai, China., Zhu D; Department of Rehabilitation Medicine, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China., Xiong ZQ; Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience and State Key Laboratory of Neuroscience, Chinese Academy of Sciences, Shanghai, China., Chen WJ; Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian, China.
Jazyk: angličtina
Zdroj: Annals of neurology [Ann Neurol] 2024 Oct; Vol. 96 (4), pp. 758-773. Date of Electronic Publication: 2024 Jul 09.
DOI: 10.1002/ana.27018
Abstrakt: Objective: Most paroxysmal kinesigenic dyskinesia (PKD) cases are hereditary, yet approximately 60% of patients remain genetically undiagnosed. We undertook the present study to uncover the genetic basis for undiagnosed PKD patients.
Methods: Whole-exome sequencing was performed for 106 PRRT2-negative PKD probands. The functional impact of the genetic variants was investigated in HEK293T cells and Drosophila.
Results: Heterozygous variants in KCNJ10 were identified in 11 individuals from 8 unrelated families, which accounted for 7.5% (8/106) of the PRRT2-negative probands. Both co-segregation of the identified variants and the significantly higher frequency of rare KCNJ10 variants in PKD cases supported impacts from the detected KCNJ10 heterozygous variants on PKD pathogenesis. Moreover, a KCNJ10 mutation-carrying father from a typical EAST/SeSAME family was identified as a PKD patient. All patients manifested dystonia attacks triggered by sudden movement with a short episodic duration. Patch-clamp recordings in HEK293T cells revealed apparent reductions in K + currents of the patient-derived variants, indicating a loss-of-function. In Drosophila, milder hyperexcitability phenotypes were observed in heterozygous Irk2 knock-in flies compared to homozygotes, supporting haploinsufficiency as the mechanism for the detected heterozygous variants. Electrophysiological recordings showed that excitatory neurons in Irk2 haploinsufficiency flies exhibited increased excitability, and glia-specific complementation with human Kir4.1 rescued the Irk2 mutant phenotypes.
Interpretation: Our study established haploinsufficiency resulting from heterozygous variants in KCNJ10 can be understood as a previously unrecognized genetic cause for PKD and provided evidence of glial involvement in the pathophysiology of PKD. ANN NEUROL 2024;96:758-773.
(© 2024 American Neurological Association.)
Databáze: MEDLINE