Ichraf Kraoua, Maha Jamoussi, Cyrine Drissi, Lilia Kraoua, Séverine Drunat, Hanene Benrhouma, Thouraya Ben Younes, Sonia Nagi, Sonia Abdelhak, Odile Boespflug Tanguy, Ilhem Ben Youssef-Turki, Mediha Trabelsi, Imen Dorboz
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引用次数: 0
Abstract
Background: POLIII-related leukodystrophies are a group of recently recognized hereditary white matter diseases with a similar clinical and radiological phenotype. No Tunisian studies have been published about POLIII-related leukodystrophy due to POLR3A variants. The aim of this study was to contribute to the clinical, radiological, and genetic characterization of POLR3A-related leukodystrophy in a Tunisian cohort.
Methods: We report six cases of genetically confirmed POLR3A-related leukodystrophy belonging to six unrelated Tunisian families, along with a review of previously published pediatric cases.
Results: All patients were born to consanguineous marriages and originated from the North or the Center of Tunisia. Age at onset varied between 15 months and 6 years. The clinical phenotype was similar in all patients with cerebellar ataxia, tremor, and nystagmus being the key features. Brain imaging showed diffuse hypomyelination in all patients with progressive cerebellar atrophy in three patients. Molecular analysis identified the same bi-allelic NM_007055.4:c.2011T>C; p.(Trp671Arg) variant in the POLR3A gene in all patients.
Conclusion: We hypothesize a founder effect for the identified variant given its recurrence in six unrelated individuals with a similar clinical phenotype. Given the apparent genetic homogeneity of Tunisian POLR3A patients, the recurrent variant should be directly targeted. This should facilitate diagnosis in index patients, and genetic counseling.
期刊介绍:
Molecular Genetics & Genomic Medicine is a peer-reviewed journal for rapid dissemination of quality research related to the dynamically developing areas of human, molecular and medical genetics. The journal publishes original research articles covering findings in phenotypic, molecular, biological, and genomic aspects of genomic variation, inherited disorders and birth defects. The broad publishing spectrum of Molecular Genetics & Genomic Medicine includes rare and common disorders from diagnosis to treatment. Examples of appropriate articles include reports of novel disease genes, functional studies of genetic variants, in-depth genotype-phenotype studies, genomic analysis of inherited disorders, molecular diagnostic methods, medical bioinformatics, ethical, legal, and social implications (ELSI), and approaches to clinical diagnosis. Molecular Genetics & Genomic Medicine provides a scientific home for next generation sequencing studies of rare and common disorders, which will make research in this fascinating area easily and rapidly accessible to the scientific community. This will serve as the basis for translating next generation sequencing studies into individualized diagnostics and therapeutics, for day-to-day medical care.
Molecular Genetics & Genomic Medicine publishes original research articles, reviews, and research methods papers, along with invited editorials and commentaries. Original research papers must report well-conducted research with conclusions supported by the data presented.