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Date Published: 05/02/2024
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DOI: https://doi.org/10.51298/vmj.v535i1.8586
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Vol. 535 No. 1 (2024)
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Các bài báo
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Lưu , T. C. ., Trần , T. C. M. ., Tạ , V. T. ., & Bùi , T. B. . (2024). IDENTIFYING MUTATIONS IN THE SLC22A5 GENE CAUSES PRIMARY CARNITINE DEFICIENCY IN PATIENTS WITH SUSPECTED NEWBORN SCREENING RESULTS. Vietnam Medical Journal, 535(1). https://doi.org/10.51298/vmj.v535i1.8586

IDENTIFYING MUTATIONS IN THE SLC22A5 GENE CAUSES PRIMARY CARNITINE DEFICIENCY IN PATIENTS WITH SUSPECTED NEWBORN SCREENING RESULTS

Thị Chiêm Lưu , Thị Chi Mai Trần , Văn Thạo Tạ , Thị Bảo Bùi

Main Article Content

Abstract

Primary Carnitine Deficiency (PCD) is a genetic disorder resulting from a reduction or loss of the ability to transport carnitine by the OCTN2 on cell membranes, leading to low serum carnitine levels and reduced intracellular carnitine accumulation. Homozygous or heterozygous mutations in the SLC22A5 gene on chromosome 5q31 are known to be the cause of this disorder. PCD is typically identified in infants when patients present with metabolic decompensation, low blood sugar, decreased ketones, or sudden death. Older children may exhibit muscular or cardiac pathology. In this study, we report a case of a 10-month-old boy diagnosed with PCD. Screening for the metabolic disorder was performed using mass spectrometry (MS) on a dried blood sample, which yielded the following results: carnitine (C0) concentration was 2.85 µmol/L (reference range 8.5 ~ 59 µmol/L), propionyl carnitine (C3) was 0.09 µmol/L (reference range 0.21 ~ 4.74 µmol/L), acetylcarnitine (C2) was 3.00 µmol/L (reference range 3.7 ~ 52 µmol/L), tetradecanoylcarnitine (C14) was 0.01 µmol/L (reference range 0.03 ~ 0.5 µmol/L), and hexadecanoylcarnitine (C16) was 0.17 µmol/L (reference range 0.41 ~ 0.6 µmol/L). After sequencing the SLC22A5 gene, the patient was found to carry a homozygous mutation (rs11568520) resulting in the substitution of the phenylalanine with leucine at codon 17 of the OCTN2 protein (p.Phe17Leu), leading to reduced carnitine transport capacity of OCTN2 into cells, causing PCD.

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References

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