A New Case of Kilquist's Syndrome with a Novel Variant in SLC12A2 and a Brief Review of the Literature

Abstract

Background Kilquist's syndrome is a recently described rare disease characterized by hearing loss, secretory dysfunction, gastrointestinal system abnormalities, and neurological anomalies including hypotonia and global developmental delay. It is caused by mutations in the solute carrier family 12 member 2 (SLC12A2) gene, which encodes the Na-K-2Cl cotransporter isoform 1 (NKCC1).

Objective The aim of this study was to contribute to understanding the genotype–phenotype correlations of SLC12A2 variants.

Material and Methods We evaluated a Turkish patient with a novel variant in SLC12A2 and reviewed all previously reported cases with Kilquist's syndrome. Whole exome sequencing and Sanger sequencing were used as molecular genetic testing methods.

Results Whole exome sequencing revealed a nonsense homozygous NM_001046.3: c.2534G > A (pW845*) variant in the SLC12A2 gene. Sanger sequencing confirmed the variant. The patient was homozygous for this variant; the parents were heterozygous.

Conclusion This is the first Turkish patient with a novel variant in SLC12A2 reported in the literature. With this report, we have contributed to expanding the clinical and mutation spectrum of SLC12A2.

Keywords

SLC12A2 - Kilquist's syndrome - NKCC1 - novel - developmental delay

Ethical Statement

Samples from the patient were obtained in accordance with the Helsinki Declaration. The paper is exempt from ethical committee approval. Ethical approval was not required for this study in accordance with local/national guidelines. Written informed consent for genetic testing was obtained from the patient's parents. Written informed consent was obtained from the parent/legal guardian of the patient for publication of the details of their medical case and any accompanying images.

Data Availability Statement

All data generated or analyzed during this study are included in the references. Further inquiries can be directed to the corresponding author.

Publikationsverlauf

Eingereicht: 03. Juli 2024

Angenommen: 25. November 2024

Artikel online veröffentlicht:
28. Dezember 2024

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