Novel heterozygous mutation of SLC12A3 gene in Gitelman syndrome.

BACKGROUND Gitelman syndrome (GS) is an autosomal recessive disease primarily caused by mutations in the SLC12A3 gene, characterized by the hypokalaemic metabolic alkalosis with hypomagnesemia. Here, we investigated the mutation of SLC12A3 gene in a Chinese pedigree with GS and analyzed the clinical manifestations. CASE PRESENTATION We present the case of a 17-year-old boy diagnosed of GS due to persistent hypokalaemia. To confirm the diagnosis of the proband and to screen for the SLC12A3 gene mutation in this pedigree, we performed SLC12A3 gene mutation tests in the 5 family members. A novel compound heterozygous mutation SLC12A3 (c.976 (exon8) de1G and c.506-1G>A (IVS3)) was identified by genetic testing in the proband. His mother is a carrier of a variant (c.506-1G>A (IVS3)), and his grandmother, father, and younger sister are the carriers of the other mutation (c.976 (exon8) de1G; p. A322_V326delinsDRNFF). His pedigree members had no GS- related symptoms. CONCLUSION This is the first study to report the novel pathogenic compound heterozygous mutation of SLC12A3 gene in GS, which could extend the spectrum of known SLC12A3 gene mutations and provide further insight into the heterogeneity of GS.