Betül Okur Altındaş, Ayse Gul Zamani, Figen Güney, Mahmut Selman Yildirim
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引用次数: 0
Abstract
Myotonia congenita is a rare genetic disorder characterized by skeletal muscle membrane hyperexcitability due to CLCN1 mutations. It can be inherited in either an autosomal dominant (Thomsen disease) or autosomal recessive (Becker disease) manner. This study describes a homozygous null alteration and its segregation analysis, confirming its pathogenicity. A 30-year-old male, presenting with myotonia since the age of five, was referred to the Medical Genetics clinic. His parents were from the same village, and two of his siblings exhibited similar symptoms. Clinical evaluation was consistent with Becker's myotonia. Next-generation sequencing revealed a homozygous nonsense variant in CLCN1 (NM_000083.2:c.450 C > A, p.Tyr150Ter [Y150*]), which was confirmed by Sanger sequencing in both the proband and his affected brother. This variant has been reported in only five patients. Given that all cases were of Turkish origin and exhibited Becker-type myotonia, our findings support a potential genotype-phenotype association and raise the possibility that this variant may be relatively more prevalent in patients from Türkiye.
期刊介绍:
Peer-reviewed and published quarterly, Acta Neurologica Belgicapresents original articles in the clinical and basic neurosciences, and also reports the proceedings and the abstracts of the scientific meetings of the different partner societies. The contents include commentaries, editorials, review articles, case reports, neuro-images of interest, book reviews and letters to the editor.
Acta Neurologica Belgica is the official journal of the following national societies:
Belgian Neurological Society
Belgian Society for Neuroscience
Belgian Society of Clinical Neurophysiology
Belgian Pediatric Neurology Society
Belgian Study Group of Multiple Sclerosis
Belgian Stroke Council
Belgian Headache Society
Belgian Study Group of Neuropathology