title: Exonic mutations in the SLC12A3 gene cause exon skipping and premature termination in Gitelman syndrome.
abstract: A variety of genetic backgrounds cause the loss of function of thiazide-sensitive sodium chloride cotransporter, encoded by SLC12A3, responsible for the phenotypes in Gitelman syndrome. Recently, the phenomenon of exon skipping, in which exonic mutations result in abnormal splicing, has been associated with various diseases. Specifically, mutations in exonic splicing enhancer (ESE) sequences can promote exon skipping. Here, we used a bioinformatics program to analyze 88 missense mutations in the SLC12A3 gene and identify candidate mutations that may induce exon skipping. The three candidate mutations that reduced ESE scores the most were further investigated by minigene assay, and two (p.A356V and p.M672I) caused abnormal splicing in vitro. Furthermore, we identified the p.M672I (c.2016G>A) mutation in a patient with Gitelman syndrome and found that this single nucleotide mutation causes exclusion of exon 16 in the SLC12A3 mRNA transcript. Functional analyses revealed that the protein encoded by the aberrant SLC12A3 transcript does not transport sodium. These results suggest that aberrant exon skipping is one previously unrecognized mechanism by which missense mutations in SLC12A3 can lead to Gitelman syndrome.
authors: Department of Clinical Biology and Hormonal Regulation and Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan;
authors: Yoichi
authors: Y
authors: Takeuchi
authors: Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan;
authors: Eikan
authors: E
authors: Mishima
authors: Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan;
authors: Hisato
authors: H
authors: Shima
authors: Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan;
authors: Yasutoshi
authors: Y
authors: Akiyama
authors: Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan;
authors: Chitose
authors: C
authors: Suzuki
authors: Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan;
authors: Takehiro
authors: T
authors: Suzuki
authors: Department of Biochemistry, Institute of Development, Aging and Cancer, and.
authors: Takayasu
authors: T
authors: Kobayashi
authors: Department of Education and Training, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan;
authors: Yoichi
authors: Y
authors: Suzuki
authors: Division of Laboratory Medicine, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan;
authors: Tomohiro
authors: T
authors: Nakayama
authors: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan; and.
authors: Yasuhiro
authors: Y
authors: Takeshima
authors: Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.
authors: Norma
authors: N
authors: Vazquez
authors: Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan;
authors: Sadayoshi
authors: S
authors: Ito
authors: Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.
authors: Gerardo
authors: G
authors: Gamba
authors: Department of Clinical Biology and Hormonal Regulation and Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan; takaabe@med.tohoku.ac.jp.
authors: Takaaki
authors: T
authors: Abe
mesh_terms: D000328:Adult; D002460:Cell Line; D005091:Exons; D005260:Female; D053579:Gitelman Syndrome / Q000235:genetics* / Q000503:physiopathology; D006801:Humans; D020125:Mutation, Missense; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D017422:Sequence Analysis, DNA; D064486:Solute Carrier Family 12, Member 3 / Q000235:genetics; D061806:Transcription Termination, Genetic
chemical_list: D012333:RNA, Messenger; C578874:SLC12A3 protein, human; D064486:Solute Carrier Family 12, Member 3
keywords: Gitelman‘s syndrome; genetic renal disease; hypokalemia