Expanded phenotype of AARS1-related white matter disease

Guy Helman, Marisa I. Mendes, Francesco Nicita, Lama Darbelli, Omar Sherbini, Travis Moore, Alexa Derksen, Pizzino Amy Pizzino, Rosalba Carrozzo, Alessandra Torraco, Michela Catteruccia, Chiara Aiello, Paola Goffrini, Sonia Figuccia, Desiree E.C. Smith, Kinga Hadzsiev, Andreas Hahn, Saskia Biskup, Ines Brösse, Urania KotzaeridouDarja Gauck, Theresa A. Grebe, Frances Elmslie, Karen Stals, Rajat Gupta, Enrico Bertini, Isabelle Thiffault, Ryan J. Taft, Raphael Schiffmann, Ulrich Brandl, Tobias B. Haack, Gajja S. Salomons, Cas Simons, Geneviève Bernard, Marjo S. van der Knaap, Adeline Vanderver*, Ralf A. Husain

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Purpose: Recent reports of individuals with cytoplasmic transfer RNA (tRNA) synthetase-related disorders have identified cases with phenotypic variability from the index presentations. We sought to assess phenotypic variability in individuals with AARS1-related disease. Methods: A cross-sectional survey was performed on individuals with biallelic variants in AARS1. Clinical data, neuroimaging, and genetic testing results were reviewed. Alanyl tRNA synthetase (AlaRS) activity was measured in available fibroblasts. Results: We identified 11 affected individuals. Two phenotypic presentations emerged, one with early infantile–onset disease resembling the index cases of AARS1-related epileptic encephalopathy with deficient myelination (n = 7). The second (n = 4) was a later-onset disorder, where disease onset occurred after the first year of life and was characterized on neuroimaging by a progressive posterior predominant leukoencephalopathy evolving to include the frontal white matter. AlaRS activity was significantly reduced in five affected individuals with both early infantile–onset and late-onset phenotypes. Conclusion: We suggest that variants in AARS1 result in a broader clinical spectrum than previously appreciated. The predominant form results in early infantile–onset disease with epileptic encephalopathy and deficient myelination. However, a subgroup of affected individuals manifests with late-onset disease and similarly rapid progressive clinical decline. Longitudinal imaging and clinical follow-up will be valuable in understanding factors affecting disease progression and outcome.

Original languageEnglish
Pages (from-to)2352-2359
Number of pages8
JournalGenetics in Medicine
Issue number12
Publication statusPublished - Dec 2021

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