1.Identification of pathological variants of SLC12A3 gene in a pedigree affected with Gitelman syndrome.
Qian MA ; Jinlin WU ; Lingyi CHE ; Xiangdong KONG
Chinese Journal of Medical Genetics 2020;37(12):1368-1370
OBJECTIVE:
To detect pathological variants of the SLC12A3 gene in a Chinese pedigree affected with Gitelman syndrome (GS).
METHODS:
Clinical data and peripheral blood samples of the proband and his family members were collected. All exons of the SLC12A3 gene were amplified by PCR and subjected to Sanger sequencing.
RESULTS:
Sanger sequencing has revealed that the proband has carried a c.486_489 delTACG (p.Ile162Met fs*8) deletion and a heterozygous c.2890C>T (p.Arg964Trp) missense variant in the SLC12A3 gene. Neither variant was reported previously and was not found among healthy controls.
CONCLUSION
The c.486_489delTACG (p.Ile162Met fs*8) and c.2890C>T (p.Arg964Trp) variants of the SLC12A3 gene probably underlay the GS in the proband. Above discovery has enriched the variant spectrum of GS.
China
;
Gitelman Syndrome/genetics*
;
Heterozygote
;
Humans
;
Mutation/genetics*
;
Pedigree
;
Solute Carrier Family 12, Member 3/genetics*
2.Whole-exome sequencing in diagnosing 2 cases of Gitelman syndrome.
Rongrong XIE ; Ping JIN ; Youbo YANG ; Qin ZHANG ; Jing XIONG
Journal of Central South University(Medical Sciences) 2022;47(3):401-406
Two patients with Gitelman syndrome were admitted to the Department of Endocrinology, Third Xiangya Hospital of Central South University. The genomic DNA from the patients' peripheral blood was extracted and the whole-exome sequencing was performed to detect the possible mutations. The function of the mutation sites was analyzed by bioinformatics software. Through whole-exome sequencing and Sanger sequencing, we have found that 2 patients with Gitelman syndrome carried compound heterozygous mutations of SLC12A3 gene, which were c.486_490delTACGGinsA, p.R943W, p.D486N, and p.R928C. Among them, c.486_490delTACGGinsA insertion deletion mutation causes frame shift and protein truncation. The p.R943W, p.D486N, and p.R928C of SLC12A3 gene were predicted to be pathogenic mutations by SIFT, PolyPhen2, and Mutation Taster. These 4 mutations were all reported, but p.R943W was first reported in Chinese population. Gitelman syndrome is rare in clinic and the rate of missed diagnosis is high. Early genetic analysis in patients with Gitelman syndrome is helpful to determine the etiology and guide the treatment.
Genetic Testing
;
Gitelman Syndrome/genetics*
;
Humans
;
Mutation
;
Pedigree
;
Solute Carrier Family 12, Member 3/genetics*
;
Whole Exome Sequencing
3.Analysis of clinical features and genetic variants among 12 children with Gitelman syndrome.
Qian DONG ; Fuying SONG ; Guohong LI ; Mu DU ; Xiaobo CHEN
Chinese Journal of Medical Genetics 2021;38(6):526-530
OBJECTIVE:
To summarize clinical manifestations and results of genetic testing in 12 children with Gitelman syndrome (GS).
METHODS:
Clinical data of the children was collected. Whole exome sequencing(WES) was carried out to screen potential variants of genomic DNA. Candidate variants were verified by Sanger sequencing.
RESULTS:
The patients have included 10 boys and 2 girls, whom were diagnosed at between 2.8 to 15.0 year old. Six patients were due to infections, 5 were due to short stature, and 1 was due to lower limb weakness. All patients were found to carry variants of SLC12A3 gene, which included 11 with compound heterozygous variants and 1 with homozygous variant. All of the 19 alleles of the SLC12A3 gene carried by the patients were delineated, which included 15 missense variants, 2 frameshift variants and 2 splice region variants. These variants were unreported previously, which included c.578_582dupCCACC (p.Asn195Profs*109), c.251C>T (p.Pro84Leu) and c.2843G>A (p.Trp948X).
CONCLUSION
The clinical symptoms of GS in children are atypical and often seen in older children. For children with occasional hypokalemia associated with growth failure, GS should be suspected. The majority of GS children carry two pathogenic variants of the SLC12A3 gene, mainly compound heterozygotes, among which p.Thr60Met is the most common one. The discovery of new variants has enriched the spectrum of SLC12A3 gene variants.
Adolescent
;
Child
;
Child, Preschool
;
DNA
;
Female
;
Genetic Testing
;
Gitelman Syndrome/genetics*
;
Humans
;
Hypokalemia/genetics*
;
Male
;
Solute Carrier Family 12, Member 3/genetics*
4.Correlation between genotypes with metabolic markers and microstructure of bones in children with Gitelman syndrome.
Mingying ZHANG ; Le HUANG ; Xiaoping JIANG ; Ling LYU ; Yan ZHAO ; Ying ZHONG ; Long GAO
Chinese Journal of Medical Genetics 2021;38(11):1087-1090
OBJECTIVE:
To explore the correlation between the genotypes and metabolic markers and microstructure of bones in children with Gitelman syndrome (GS).
METHODS:
For 15 children with GS and 10 healthy individuals, baseline data and bone metabolic markers including parathyroid hormone, alkaline phosphatase, osteocalcin, N-terminal propeptide of type I procollagen, beta isomer of the C-terminal telopeptide of type I collagen and 25-hydroxyvitamin D, high-resolution peripheral quantitative computed tomography indicators (volumetric bone mineral density, bone microstructure indicators) were collected. Genetic testing was carried out to determine their genotypes.
RESULTS:
The volumetric bone mineral density, bone geometry and bone microstructure parameters of the GS group were better than those of the healthy controls (P<0.05). Variants of the SLC12A3 gene were identified in 9 of the 15 patients but none of the 10 healthy controls.
CONCLUSION
The phenotype of GS children is influenced by the interaction of genetic variants, though the phenotype associated with high frequency mutations showed no specificity. There is also a correlation between their genotype and the bone microstructure.
Biomarkers
;
Bone and Bones
;
Child
;
Collagen Type I/genetics*
;
Genotype
;
Gitelman Syndrome
;
Humans
;
Osteocalcin/genetics*
;
Peptide Fragments
;
Solute Carrier Family 12, Member 3
5.Clinical and genetic analysis of a case of Gitelman syndrome with comorbid Graves disease and adrenocortical adenoma.
Yan QIAO ; Jinghong ZHAO ; Lewei CAO ; Yunxiang LI ; Ji WU
Chinese Journal of Medical Genetics 2023;40(11):1409-1413
OBJECTIVE:
To report the clinical and genetic characteristics of a rare case of Gitelman syndrome with comorbid Graves disease and ACTH-independent adrenocortical adenoma.
METHODS:
A patient who had presented at the Nanchong Central Hospital on December 21, 2020 was selected as the study subject. Clinical data of the patient was collected. Whole-exome sequencing was carried out on DNA extracted from peripheral venous blood samples from the patient and her family members.
RESULTS:
The patient, a 45-year-old woman, was found to have Graves disease, ACTH-independent Cushing syndrome, hypokalemia and hypomagnesemia following the discovery of an adrenal incidentaloma. MRI scan had revealed a 3.8 cm × 3.2 cm mass in the left adrenal gland. The mass was removed by surgery and confirmed as adrenocortical adenoma. DNA sequencing revealed that the patient and her sister have both harbored compound heterozygous variants of the SLC12A3 gene, namely c.1444-10(IVS11)G>A and c.179(exon1)C>T (p.T60M), which were respectively inherited from their father and mother. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.1444-10(IVS11)G>A and c.179(exon1)C>T (p.T60M) were respectively classified as a variant of uncertain significance (PM2_Supporting+PP3) and a likely pathogenic variant (PM3_Strong+PM1+PP3).
CONCLUSION
The conjunction of Gitelman syndrome with Graves disease and adrenal cortex adenoma is rather rare. The newly discovered c.1444-10(IVS11)G>A variant of the SLC12A3 gene, together with the heterozygous variant of c.179(exon1)C>T (p.T60M), probably underlay the pathogenesis in this patient.
Humans
;
Female
;
Middle Aged
;
Gitelman Syndrome/genetics*
;
Adrenocortical Adenoma
;
Hypokalemia
;
Graves Disease/genetics*
;
Mothers
;
Mutation
;
Solute Carrier Family 12, Member 3
6.Value of Chloride Clearance Test in Differential Diagnosis of Gitelman Syndrome.
Xiao-yan PENG ; Lan-ping JIANG ; Tao YUAN ; Cai YUE ; Ke ZHENG ; Ou WANG ; Nai-shi LI ; Wei LI ; An-li TONG ; Xiao-ping XING ; Xue-mei LI ; Xue-wang LI ; Li-meng CHEN
Acta Academiae Medicinae Sinicae 2016;38(3):275-282
Objective To investigate the value of chloride clearance test in differential diagnosis of Gitelman syndrome (GS). Methods For patients with hypokalemic metabolic alkalosis and highly suspected GS,clinical data were documented and SLC12A3 gene screening was performed as gold standard to diagnose GS. Hydrochlorothiazide (HCT) test and furosemide (FUR) test were performed according to the standard process. Baseline and maximal increasement of chloride excretion fraction (FECl,the net and relative increase measured as εFECl) were compared between patients and controls to evaluated the reaction to the corresponding diuretics. Receiver operating characteristic (ROC) curve was used to evaluate the sensitivity and specificity of HCT test in GS diagnosis. Results Totally 27 patients and 20 health controls received HCT test. Among those patients,23 were diagnosed with GS genetically. When using the net and relative εFECl to diagnose GS,the areas under the ROC curve were 0.987 (95% CI:0.963~1.000,P<0.001) and 0.984 (95%CI:0.950~1.000,P<0.001),respectively. When a reasonable cutoff value for εFECl was selected,the sensitivity and specificity were both higher than 95%. Eight patients received both HCT test and FUR test. Five of them showed decreased reaction to HCT(net εFECl≤2.86% or relative εFECl≤223%),while normal reaction to FUR.SLC12A3 mutations confirmed their GS. Three patients with blunt reaction to FUR showed normal reaction to HCT,finally they were diagnosed as BS clinically because no SLC12A3 gene mutation was detected. Conclusion Comprehensive application of HCT test and FUR test to evaluate the diuretic reaction can effectively differentiate GS and BS.
Case-Control Studies
;
Chlorides
;
metabolism
;
Diagnosis, Differential
;
Gitelman Syndrome
;
diagnosis
;
Humans
;
Hydrochlorothiazide
;
Kinetics
;
Mutation
;
ROC Curve
;
Sensitivity and Specificity
;
Solute Carrier Family 12, Member 3
;
genetics
;
metabolism
7.Mutations in SLC12A3 and CLCNKB and Their Correlation with Clinical Phenotype in Patients with Gitelman and Gitelman-like Syndrome.
Jae Wook LEE ; Jeonghwan LEE ; Nam Ju HEO ; Hae Il CHEONG ; Jin Suk HAN
Journal of Korean Medical Science 2016;31(1):47-54
Gitelman's syndrome (GS) is caused by loss-of-function mutations in SLC12A3 and characterized by hypokalemic metabolic alkalosis, hypocalciuria, and hypomagnesemia. Long-term prognosis and the role of gene diagnosis in GS are still unclear. To investigate genotype-phenotype correlation in GS and Gitelman-like syndrome, we enrolled 34 patients who showed hypokalemic metabolic alkalosis without secondary causes. Mutation analysis of SLC12A3 and CLCNKB was performed. Thirty-one patients had mutations in SLC12A3, 5 patients in CLCNKB, and 2 patients in both genes. There was no significant difference between male and female in clinical manifestations at the time of presentation, except for early onset of symptoms in males and more profound hypokalemia in females. We identified 10 novel mutations in SLC12A3 and 4 in CLCNKB. Compared with those with CLCNKB mutations, patients with SLC12A3 mutations were characterized by more consistent hypocalciuria and hypomagnesemia. Patients with 2 mutant SLC12A3 alleles, compared with those with 1 mutant allele, did not have more severe clinical and laboratory findings except for lower plasma magnesium concentrations. Male and female patients did not differ in their requirement for electrolyte replacements. Two patients with concomitant SLC12A3 and CLCNKB mutations had early-onset severe symptoms and showed different response to treatment. Hypocalciuria and hypomagnesemia are useful markers in differentiation of GS and classical Bartter's syndrome. Gender, genotypes or the number of SLC12A3 mutant alleles cannot predict the severity of disease or response to treatment.
Adolescent
;
Adult
;
Alleles
;
Bartter Syndrome/genetics/pathology
;
Chloride Channels/*genetics
;
DNA Mutational Analysis
;
Female
;
Genetic Association Studies
;
Genotype
;
Gitelman Syndrome/*genetics/pathology
;
Humans
;
Hypokalemia/etiology
;
Male
;
Middle Aged
;
Phenotype
;
Polymorphism, Genetic
;
Solute Carrier Family 12, Member 3/genetics
;
Young Adult