A novel heterozygous variant of the SALL1 gene with atypical Townes-Brocks syndrome phenotypes in Chinese family.

Townes-Brocks syndrome (TBS) is an autosomal dominant disorder characterised by the triad of anorectal, thumb, and ear malformations. It may also be accompanied by defects in kidney, heart, eyes, hearing, and feet. TBS has been demonstrated to result from heterozygous variants in the SALL1 gene, which encodes zinc finger protein believed to function as a transcriptional repressor.

Three exonic variants in the COL4A5 gene alter RNA splicing in a minigene assay.

Background: X-linked Alport syndrome (XLAS) is an inherited renal disease caused by rare variants of COL4A5 on chromosome Xq22. Many studies have indicated that single nucleotide variants (SNVs) in exons can disrupt normal splicing process of the pre-mRNA by altering various splicing regulatory signals. The male patients with XLAS have a strong genotype-phenotype correlation.

Four novel variants identified in primary hyperoxaluria and genotypic and phenotypic analysis in 21 Chinese patients.

Primary hyperoxaluria (PH) is a rare genetic disorder characterized by excessive accumulation of oxalate in plasma and urine, resulting in various phenotypes due to allelic and clinical heterogeneity. This study aimed to analyze the genotype of 21 Chinese patients with primary hyperoxaluria (PH) and explore their correlations between genotype and phenotype. Combined with clinical phenotypic and genetic analysis, we identified 21 PH patients from highly suspected Chinese patients.

Minigene splicing assays reveal new insights into exonic variants of the SLC12A3 gene in Gitelman syndrome.

Background: Gitelman syndrome (GS) is a type of salt-losing tubular disease, most of which is caused by SLC12A3 gene variants, and missense variants account for the majority. Recently, the phenomenon of exon skipping, in which variants disrupt normal pre-mRNA splicing, has been related to a variety of diseases. Therefore, we hypothesize that a certain proportion of SLC12A3 variants can result in disease via interfering with the normal splicing process.

Identification of two novel variants of BCS1L gene in a patient with classical GRACILE syndrome.

BCS1L pathogenic variants cause widely different clinical phenotypes. Disease phenotypes can be as mild as Björnstad syndrome, characterized by pili torti (abnormal flat twisted hair shafts) and sensorineural hearing loss, or as severe as GRACILE syndrome, characterized by growth restriction, aminoaciduria, cholestasis, iron overload, lactic acidosis and early death. BCS1L pathogenic variants are also linked to an undefined complex III deficiency, a heterogeneous condition generally involving renal and hepatic pathologies, hypotonia, and developmental delays.

Genotypic and phenotypic analysis in 51 Chinese patients with primary distal renal tubular acidosis.

The aim of this study was to analyze the genetic variants of 51 Chinese patients with distal renal tubular acidosis (dRTA) and explore the correlation between their genotype and phenotype. Eight variants of SLC4A1, 19 variants of ATP6V0A4, and 16 variants of ATP6V1B1 have been identified, and of which 14 were novel ones. Eleven patients with autosomal dominant dRTA, and four patients with autosomal recessive dRTA were caused by genetic defects in SLC4A1; 18 and nine patients with recessive dRTA were resulted by defects in ATP6V0A4 and ATP6V1B1 respectively; no causal gene was identified in seven patients.

Identification of seven exonic variants in the SLC4A1, ATP6V1B1, and ATP6V0A4 genes that alter RNA splicing by minigene assay.

Primary distal renal tubular acidosis (dRTA) is a rare tubular disease associated with variants in SLC4A1, ATP6V0A4, ATP6V1B1, FOXⅠ1, or WDR72 genes. Currently, there is growing evidence that all types of exonic variants can alter splicing regulatory elements, affecting the precursor messenger RNA (pre-mRNA) splicing process. This study was to determine the consequences of variants associated with dRTA on pre-mRNA splicing combined with predictive bioinformatics tools and minigene assay.

Eight novel KCNJ1 variants and parathyroid hormone overaction or resistance in 5 probands with Bartter syndrome type 2.

Purpose: Bartter syndrome type 2 (BS2) is an autosomal recessive renal tubular disorder, which is caused by the mutations in KCNJ1. This study was designed to analyze and describe the genotype and clinical features of five Chinese probands with BS2.

Methods: Identify KCNJ1 gene variants by the next generation sequencing and evaluate their mutation effects according to 2015 American College of Medical Genetics and Genomics (ACMG) standards and guidelines.

Sudden onset of nephrotic syndrome in an asymptomatic Fabry patient: a case report.

Background: Fabry disease (FD) is an X-linked lysosomal storage disorder caused by the mutation of the gene, encoding the α-galactosidase, which is responsible for the catabolism of neutral glycosphingolipids. Microalbuminuria or low-grade proteinuria, and continuously progressive renal failure are common manifestations in FD males. However, sudden onset of nephrotic syndrome in FD, is rarely reported.

Thirteen novel CLCNKB variants and genotype/phenotype association study in 42 Chinese patients with Bartter syndrome type 3.

Purpose: Analyze the genotype of 42 Chinese patients with Bartter syndrome type 3 (BS3) and investigate their correlation between genotype and phenotype.

Methods: Identify CLCNKB gene variants by the next-generation sequencing and the multiplex ligation-dependent probe amplification (MLPA), and then evaluate their mutation effects according to 2015 American College of Medical Genetics and Genomics (ACMG) standards and guidelines.

Results: Thirty-six different variants in CLCNKB gene, including 13 novel ones, were found.

Eleven novel SLC12A1 variants and an exonic mutation cause exon skipping in Bartter syndrome type I.

Introduction: Bartter syndrome type I (BS1) has been rarely reported in large groups. On the other hand, the phenomenon of exon skipping, in which exonic mutations result in abnormal splicing, has been reported to be associated with various diseases. Specifically, mutations that result in the disruption of exonic splicing enhancers (ESEs) and/or the creation of exonic splicing silencers (ESSs) can promote exon skipping.

Novel compound heterozygous ATP6V1B1 mutations in a Chinese child patient with primary distal renal tubular acidosis: a case report.

Background: Distal renal tubular acidosis (dRTA) is a heterogeneous disorder characterized by normal anion gap metabolic acidosis. Autosomal recessive dRTA is usually caused by mutations occurring in ATP6V1B1 and ATP6V0A4 genes,encoding subunits B1 and a4 of apical H-ATPase, respectively. The heterogeneous clinical manifestations of dRTA have been described in different ethnic groups harboring distinct mutations.

Five Novel Mutations in Chinese Children with Primary Distal Renal Tubular Acidosis.

Aim: To analyze the variants of the potential causative genes in five Chinese patients with primary distal renal tubular acidosis (dRTA) from five unrelated families, and to explore their possible genotype-phenotype correlations, so as to raise the awareness of the disease.

Methods: Variants were identified by next generation sequencing. Clinical features and biochemical findings at the first presentation, as well as at follow-up visits were also investigated.

Identification of a novel TSC2 c.3610G > A, p.G1204R mutation contribute to aberrant splicing in a patient with classical tuberous sclerosis complex: a case report.

Background: Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by hamartomas in any organ systems. Mutations in the TSC1 or TSC2 gene lead to the dysfunction of hamartin or tuberin proteins, which cause tuberous sclerosis complex.

Case Presentation: We describe the clinical characteristics of patients from a Chinese family with tuberous sclerosis complex and analyze the functional consequences of their causal genetic mutations.

Familial hypomagnesaemia, Hypercalciuria and Nephrocalcinosis associated with a novel mutation of the highly conserved leucine residue 116 of Claudin 16 in a Chinese patient with a delayed diagnosis: a case report.

Background: Sixty mutations of claudin 16 coding gene have been reported in familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) patients. Recent investigations revealed that a highly conserved glycine-leucine-tryptophan (G-L-W) motif in the first extracellular segment (ESC1) of claudin 16 might be essential for stabilization of the appropriately folded ECS1 structure and conservation of normal claudin 16 function. However, neither missense nor nonsense mutation has ever been described in this motif.

A novel mutation in exon 9 of Cullin 3 gene contributes to aberrant splicing in pseudohypoaldosteronism type II.

Pseudohypoaldosteronism type II (PHAII) is a rare renal tubular disease that is inherited in an autosomal dominant manner. Mutations in four genes (,, and ) have been identified to be responsible for this disease. Cullin 3 (CUL3) and KLHL3 are subunits of Cullin-RING E3 ubiquitin ligase complexes, and the serine-threonine kinases WNK1 and WNK4 are substrates of this ubiquitin ligase.

A recurrent deletion in the SLC5A2 gene including the intron 7 branch site responsible for familial renal glucosuria.

Familial renal glycosuria (FRG) is caused by mutations in the SLC5A2 gene, which codes for Na-glucose co-transporters 2 (SGLT2). The aim of this study was to analyze and identify the mutations in 16 patients from 8 families with FRG. All coding regions, including intron-exon boundaries, were analyzed using PCR followed by direct sequence analysis.

Two novel AGXT mutations identified in primary hyperoxaluria type-1 and distinct morphological and structural difference in kidney stones.

Primary hyperoxaluria type 1 (PH1) is a rare genetic disease characterized by excessive oxalate accumulation in plasma and urine, resulting in various phenotypes because of allelic and clinical heterogeneity. This study aimed to detect disease-associated genetic mutations in three PH1 patients in a Chinese family. All AGXT exons and 3 common polymorphisms which might synergistically interact with mutations, including P11L, I340 M and IVSI+74 bp were analyzed by direct sequencing in all family members.

Genotype/Phenotype Analysis in 67 Chinese Patients with Gitelman's Syndrome.

Background: Gitelman's syndrome (GS) is an autosomal recessive renal tubular disorder, which is caused by the mutations in SLC12A3. This study was designed to analyze the characteristics of the genotype and phenotype, and follow-up in the largest group of Chinese patients with GS.

Methods: Sixty-seven patients with GS underwent SLCl2A3 analysis, and their clinical characteristics and biochemical findings as well as follow-up were reviewed, aiming to achieve a better description of GS.

Two Novel HOGA1 Splicing Mutations Identified in a Chinese Patient with Primary Hyperoxaluria Type 3.

Background: Twenty-six HOGA1 mutations have been reported in primary hyperoxaluria (PH) type 3 (PH3) patients with c.700 + 5G>T accounting for about 50% of the total alleles. However, PH3 has never been described in Asians.

Mutation analysis and audiologic assessment in six Chinese children with primary distal renal tubular acidosis.

The objective of this study is to identify ATP6V1B1, ATP6V0A4 and SLC4A1 genes mutations and assess audiologic characteristics in six Chinese children with primary distal renal tubular acidosis from four unrelated families between the ages of 2 and 13 years. Both ATP6V0A4 and ATP6V1B1 genes were preferentially screened in all index cases by direct sequence analysis. If inconclusive then SLC4A1 gene should be analyzed for mutation.

Percutaneous Transluminal Revascularization following an Angiotensin Receptor Blocker: Successful Treatment for Flash Pulmonary Edema and Hyponatremic Hypertensive Syndrome.

Either flash pulmonary edema or hyponatremic hypertensive syndrome has been described in renal artery stenosis. However, coexistence of these two disorders has never been previously reported. We describe a patient who presented with flash pulmonary edema and hyponatremic hypertensive syndrome associated with bilateral renal artery disease (one complete occlusion, one highly critical renal artery stenosis, the equivalent of unilateral stenosis of a solitary functioning kidney).

High-frequency variant p.T60M in NaCl cotransporter and blood pressure variability in Han Chinese.

Objective: Frequent studies have confirmed that homozygous or compound heterozygous loss-of-function mutation p.Thr60Met in NaCl cotransporter (NCC) lead to the salt-wasting Gitelman's syndrome (GS) of hypotension. The finding that Thr60 is a key SPAK/OSR1 phosphorylation site on NCC also raises the possible importance of Thr60 in regulating the activity of NCC and blood pressure (BP).

A novel SLC4A1 variant in an autosomal dominant distal renal tubular acidosis family with a severe phenotype.

Mutations in SLC4A1, encoding the chloride-bicarbonate exchanger AE1, cause distal renal tubular acidosis (dRTA), a disease of defective urinary acidification by the distal nephron. We searched for SLC4A1 gene mutations in six patients from a Chinese family with a severe phenotype of dRTA (growth impairment, severe metabolic acidosis, with/or without gross nephrocalcinosis and renal impairment). All coding regions of kidney isoform of AE1, including intron-exon boundaries, were analyzed using PCR followed by direct sequence analysis.

Coexistence of normotensive primary aldosteronism in two patients with Gitelman's syndrome and novel thiazide-sensitive Na-Cl cotransporter mutations.

Background: Primary aldosteronism (PA) is the most common form of secondary hypertension, while Gitelman's syndrome (GS) is the most common inherited renal tubular disease. However, coexistence of these two diseases has never been previously reported. AIM AND SUBJECTS: The aim of our study was to describe the association of GS and PA in two unrelated patients and compare their clinical presentation with a group of patients with GS.