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Published: 2026-08-25
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DOI: https://doi.org/10.52852/tcncyh.v205i8.5729
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Vol. 205 No. 8 (2026)
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Các bài báo
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Quang, D. M., Dũng, V. C., Khánh, N. N., Mai, T. T. C., Hoài, N. Q., Lan, N. N., Phương, L. T., Việt, N. H., Thịnh, T. H., Khoa, N. X., Tú, N. H., Đức, L. M., Bắc, V. N., & Khánh, T. V. (2026). Genotype spectrum of the MMUT gene in patients with methylmalonic acidemia. Journal of Medical Research, 205(8), 93-107. https://doi.org/10.52852/tcncyh.v205i8.5729

Genotype spectrum of the MMUT gene in patients with methylmalonic acidemia

Diep Minh Quang, Vu Chi Dung, Nguyen Ngoc Khanh, Tran Thi Chi Mai, Nguyen Quy Hoai, Nguyen Ngoc Lan, Le Thi Phuong, Nguyen Hoang Viet, Tran Huy Thinh, Ngo Xuan Khoa, Nguyen Huu Tu, Le Manh Duc, Vu Ngoc Bac, Tran Van Khanh

Main Article Content

Abstract

Methylmalonic acidemia (MMA) caused by MMUT gene mutations is a severe autosomal recessive disorder of organic acid metabolism. This retrospective case series describes 6 MMA patients diagnosed at Vietnam National Children’s Hospital using tandem mass spectrometry (MS/MS), gas chromatography-mass spectrometry (GC/MS), next-generation sequencing (NGS), and Sanger sequencing. All 6 patients were admitted with acute metabolic acidosis; none were identified through newborn screening. All had elevated propionylcarnitine (C3), and five showed abnormal urinary organic acids. Genetic analysis identified 7 variants in the MMUT gene, of which the two most common were c.754-2A>G and c.581C>T p.(Pro194Leu), each occurring in 3/6 patients (50%). Disease severity tended to decrease from the mut0/mut0 group to mut0/mut− and mut−/mut− groups: mut0/mut0 was associated with higher mortality risk, mut0/mut− with neurodevelopmental delay, and mut−/mut− predominantly with progressive neurological complications. To our knowledge, this is the first study describing the MMUT variant spectrum in Vietnamese patients, highlighting the need for expanded newborn screening by MS/MS, with GC/MS as a confirmatory test and NGS as a comprehensive diagnostic platform.

Article Details

Keywords

Methylmalonic acidemia, MMUT, NGS, metabolic acidosis, newborn screening

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