Summary
We report clinical and molecular studies in three unrelated Tunisian families containing seven patients with L2HGA. Although the age of onset is similar in all these patients at nearly 6 years, they progressively developed peculiar clinical phenotypes different from family to family. The three patients of family 1 showed mental retardation, epilepsy, cerebellar ataxia and pyramidal and pseudobulbar syndromes. The two patients of family 2 showed mental retardation and parkinsonism especially extrapyramidal stiffness, dystonia and myoclonus. The two patients of family 3 showed an intermediate phenotype; they share some clinical signs of the patients of family 1 (epilepsy, pyramidal and extrapyramidal syndromes) and some clinical signs of the patients of family 2 (extrapyramidal stiffness and dystonia). Molecular study identified a novel homozygous c.185C > A, p.A62D mutation on the L2HGDH gene in families 1 and 3 and the already known homozygous c.241A > G, p.K81E mutation in family 2. We suppose that the type of mutation in the L2HGDH gene does not play a complete role in the inter-familial phenotype variability. Disturbance of other unknown metabolic pathways related to L2HGA may contribute to this phenomenon.
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Communicating editor: Cornelis Jakobs
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Larnaout, A., Amouri, R., Kefi, M. et al. l-2-Hydroxyglutaric aciduria: Clinical and molecular study in three Tunisian families. Identification of a new mutation and inter-familial phenotype variability. J Inherit Metab Dis 31 (Suppl 2), 375–379 (2008). https://doi.org/10.1007/s10545-008-0934-6
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DOI: https://doi.org/10.1007/s10545-008-0934-6