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Published: 2025-07-28
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DOI: https://doi.org/10.52852/tcncyh.v192i7.3675
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Vol. 192 No. 7 (2025)
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Các bài báo
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Huyền, V. T., Anh, L. T. L., Phượng, Đoàn T. K., Lan, H. T. N., Trang, N. T., Châu, L. M., Anh, P. N., Anh, T. T. L., Hảo, N. T., Hoài, N. T., Tùng, N. S., Phương, N. L., Hùng, V. Đình, Hường, T. T. T., Duyên, N. T., Hà , N. N., Hạnh, L. T., Giang, P. T., & Trang, Đào T. (2025). 63. Genotype-phenotype correlation in Phenylketonuria of a common gene variant PAH:c.516G>T in Vietnam: Report of four cases. Journal of Medical Research, 192(7), 599-608. https://doi.org/10.52852/tcncyh.v192i7.3675

63. Genotype-phenotype correlation in Phenylketonuria of a common gene variant PAH:c.516G>T in Vietnam: Report of four cases

Vu Thi Huyen, Luong Thi Lan Anh, Doan Thi Kim Phuong, Hoang Thi Ngoc Lan, Nguyen Thi Trang, Le Minh Chau, Phan Ngoc Anh, Ta Thi Lan Anh, Nguyen Thi Hao, Nguyen Thi Hoai, Nguyen Son Tung, Nguyen Lan Phuong, Vu Dinh Hung, Tran Thi Thu Huong, Nguyen Thi Duyen, Nguyen Ngan Ha, Le Thi Hanh, Pham Truong Giang, Dao Thi Trang

Main Article Content

Abstract

The c.516G>T (p.Gln172His) variant in the PAH gene is the most prevalent variant in the Vietnamese population, yet clinical data on its phenotypic impact remain extremely limited. We report four cases carrying this variant in either compound heterozygous or homozygous states, identified through a prenatal carrier screening program. Two cases were compound heterozygotes with c.516G>T in trans with previously classified pathogenic variants, while the remaining two were homozygous for c.516G>T. All individuals were asymptomatic with no clinical abnormality and had mildly elevated or normal phenylalaninemia levels, consistent with mild hyperphenylalaninemia (MHPA) or a clinically normal state; none required dietary restriction or medical intervention. These findings suggest that the PAH:c.516G>T variant may be associated with a mild phenotype or limited functional impact, even in homozygosity. This has important implications for clinical genetics practice in Vietnam, particularly in prenatal counseling, as it may help prevent unnecessary interventions or overestimated prenatal diagnosis, and ensure proper postnatal follow-up.

Article Details

Keywords

Phenylketonuria, mild hyperphenylalaninemia, c.516G>T, p.Gln172His, PAH

References

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