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Published: 2026-08-04
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DOI: https://doi.org/10.52852/tcncyh.v204i7.5535
Issue
Vol. 204 No. 7 (2026)
Section
Các bài báo
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My, P. T. T., Khánh, T. V., Tú, N. H., Dũng, V. C., Khánh, N. N., Lan, N. N., Phương, L. T., Thúy, N. T. P., & Tuấn, P. L. A. (2026). Identification of SLC22A5 mutations and pedigree analysis in families of newborns suspected of primary Carnitine deficiency. Journal of Medical Research, 204(7), 628-638. https://doi.org/10.52852/tcncyh.v204i7.5535

Identification of SLC22A5 mutations and pedigree analysis in families of newborns suspected of primary Carnitine deficiency

Phan Thi Thao My, Tran Van Khanh, Nguyen Huu Tu, Vu Chi Dung, Nguyen Ngoc Khanh, Nguyen Ngoc Lan, Le Thi Phuong, Nguyen Thi Phuong Thuy, Pham Le Anh Tuan

Main Article Content

Abstract

Primary carnitine deficiency (PCD) is an autosomal recessive inherited disorder caused by mutations in the SLC22A5 gene, which function is to encode the organic cation transporter novel type 2 (OCTN2); gene mutation leads to reduced plasma carnitine levels. Currently, the diagnosis of PCD is mainly based on biochemical testing combined with clinical manifestations, which are not sufficiently specific to distinguish PCD from other disorders. Therefore, this study was conducted to identify SLC22A5 gene mutations in four families, including four patients with tandem mass spectrometry (MS/MS) screening results suggestive of primary carnitine deficiency and 11 first-degree biological relatives. Using Sanger sequencing, three SLC22A5 mutations were identified, including c.760C>T (p.Arg254*), c.51C>G (p.Phe17Leu), and c.338G>A (p.Cys113Tyr). Pedigree analysis demonstrated the hereditary nature of these mutations within families and identified asymptomatic carriers of disease-associated variants. The findings highlight the important role of molecular genetic testing in the definitive diagnosis of PCD and in providing genetic counseling for at-risk families.

Article Details

Keywords

Primary carnitine deficiency, SLC22A5 gene, genetic screening

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