Objective: To clarify the phenotypes of the newborns with SLC26A4 single-allele mutation in deafness genetic screening and second variant; to analyze the SLC26A4 genotype and hearing phenotype. Methods: 850 newborns born in Beijing from April 2015 to December 2019 were included and there were 468 males and 382 females. They received genetic deafness screening for 9 or 15 variants, with the result of SLC26A4 single-allele mutation. Firstly, three step deafness gene sequencing was adopted in this work, i.e., the first step was "SLC26A4 gene whole exons and splice sites" sequencing; the second step was "SLC26A4 gene promoter, FOXI1 gene and KCNJ10 gene whole exons" sequencing; and the third step was detection for "SLC26A4 gene copy number variation". Secondly, we collected the results of newborn hearing screening for all patients with the second mutation found in the three step test, and conducted audiological examinations, such as acoustic immittance, auditory brainstem response and auditory steady state response. Thirdly, for novel/VUS mutations, we searched the international deafness gene database or software, such as DVD, ClinVar and Mutation Taster, to predict the pathogenicity of mutations according to the ACMG guideline. Lastly, we analyzed the relationship between genotype and phenotype of newborns with SLC26A4 single allele mutation. Results: Among 850 cases, the median age of diagnosis was 4 months. In the first step, 850 cases were sequenced. A total of 32 cases (3.76%, 32/850) of a second variants were detected, including 18 cases (2.12%, 18/850) with identified pathogenic variants; 832 cases were sequenced and 8 cases of KCNJ10 gene missense variants were detected among the second step. No missense mutations in the FOXI1 gene and abnormal SLC26A4 gene promoter were detected; the third step sequencing results were all negative. Genotypes and hearing phenotypes included 18 cases combined with the second clear pathogenic variant, 16 cases (16/18) referred newborn hearing screening and 2 cases (2/18) passed in both ears; degree of hearing loss consisted of 18 profound ears (18/36), 13 severe ears (13/36) and 5 moderate ears (5/36); audiogram patterns comprised 17 high frequency drop ears (17/36), 14 flat ears (14/36), 3 undistinguished ears (3/36), and 2 U shaped ears (2/36); 11 cases underwent imaging examination, all of which were bilateral enlarged vestibular aqueduct. As for 22 cases of other genotypes, all passed neonatal hearing screening and the hearing diagnosis was normal, including 9 cases with VUS or possibly novel benign variants, 8 cases with KCNJ10 double gene heterozygous variants, and 5 cases with double heterozygous variants. Conclusions: The probability of individuals with SLC26A4 single-allele variant who merge with a second pathogenic variant is 2.12%, all of which are SNV, which can provide scientific basis for the genetic diagnosis and genetic counseling of SLC26A4 variants. Those who have merged with second pathogenic variant are all diagnosed with sensorineural hearing loss. Patients with KCNJ10 gene mutations do not manifest hearing loss during the infancy, suggesting the need for further follow-up.
Female ; Humans ; Male ; Alleles ; Deafness/genetics* ; DNA Copy Number Variations ; Forkhead Transcription Factors/genetics* ; Genotype ; Hearing Loss/genetics* ; Hearing Loss, Sensorineural/genetics* ; Mutation ; Phenotype ; Sulfate Transporters/genetics* ; Vestibular Aqueduct ; Infant, Newborn ; Potassium Channels, Inwardly Rectifying/genetics*

OBJECTIVES: Epilepsy is a syndrome of central nervous system dysfunction caused by many reasons, which is mainly characterized by abnormal discharge of neurons in the brain. Therefore, finding new targets for epilepsy therapy has always been the focus and hotspot in neurological research field. Studies have found that 2-deoxy-D-glucose (2-DG) exerts anti-epileptic effect by up-regulation of K_ATP channel subunit Kir6.1, Kir6.2 mRNA and protein. By using the database of TargetScan and miRBase to perform complementary pairing analysis on the sequences of miRNA and related target genes, it predicted that miR-194 might be the upstream signaling molecule of K_ATP channel. This study aims to explore the mechanism by which 2-DG exerts its anti-epileptic effect by regulating K_ATP channel subunits Kir6.1 and Kir6.2 via miR-194. METHODS: A magnesium-free epilepsy model was established and randomly divided into a control group, an epilepsy group (EP group), an EP+2-DG group, and miR-194 groups (including EP+miR-194 mimic, EP+miR-194 mimic+2-DG, EP+miR-194 mimic control, EP+miR-194 inhibitor, EP+miR-194 inhibitor+2-DG, and EP+miR-194 inhibitor control groups). The 2-DG was used to intervene miR-194 mimics, patch-clamp method was used to detect the spontaneous recurrent epileptiform discharges, real-time PCR was used to detect neuronal miR-194, Kir6.1, and Kir6.2 expressions, and the protein levels of Kir6.1 and Kir6.2were detected by Western blotting. RESULTS: Compared with the control group, there was no significant difference in the amplitude of spontaneous discharge potential in the EP group (P>0.05), but the frequency of spontaneous discharge was increased (P<0.05). Compared with the EP group, the frequency of spontaneous discharge was decreased (P<0.05). Compared with the EP+miR-194 mimic control group, the mRNA and protein expressions of Kir6.1 and Kir6.2 in the EP+miR-194 mimic group were down-regulated (all P<0.05). Compared with the EP+miR-194 inhibitor control group, the mRNA and protein expressions of Kir6.1 and Kir6.2 in the EP+miR-194 inhibitor group were up-regulated (all P<0.05). After pretreatment with miR-194 mimics, the mRNA and protein expression levels of K_ATP channel subunits Kir6.1 and Kir6.2 were decreased (all P<0.05). Compared with the EP+2-DG group, the mRNA and protein expression levels of Kir6.1 and Kir6.2 in the EP+miR-194 mimic+2-DG group were down-regulated (all P<0.05) and the mRNA and protein expression levels of Kir6.1 and Kir6.2 in the EP+miR-194 inhibitor+2-DG group were up-regulated (all P<0.05). CONCLUSIONS The 2-DG might play an anti-epilepsy effect by up-regulating K_ATP channel subunits Kir6.1 and Kir6.2via miR-194.
Adenosine Triphosphate ; Anticonvulsants ; Deoxyglucose/pharmacology* ; Epilepsy/genetics* ; Glucose ; Humans ; MicroRNAs/genetics* ; Potassium Channels, Inwardly Rectifying/metabolism* ; RNA, Messenger/metabolism* ; Signal Transduction

OBJECTIVE: To investigate the clinical characteristics and genetic basis for a child with Keppen-Lubinsky syndrome (KPLBS). METHODS: Trio-whole exome sequencing (Trio-WES) was carried out for the proband and her parents. Candidate variant was verified by Sanger sequencing and bioinformatic analysis. RESULTS: The child has featured peculiar facies including large eyes, alar hypoplasia, microretrognathia, premature aging appearance in addition with growth delay and mental retardation. Trio-WES has identified that she has carried a de novo variant of the KCNJ6 gene, namely c.460G>C (p.Gly154Arg). The variant has not been recorded in the database. Prediction of protein structure indicated that the variant may affect the potassium ion selective filtration structure channel in the transmembrane region of KCNJ6 protein, which may result in up regulation of the function of the channel. CONCLUSION The de novo c.460G>C (p.Gly154Arg) variant of the KCNJ6 gene probably underlay the KPLBS in this child. Above finding has enriched the genotypic and phenotype spectrum of this syndrome.
Cataract ; China ; Female ; G Protein-Coupled Inwardly-Rectifying Potassium Channels/genetics* ; Humans ; Hypogonadism/congenital* ; Intellectual Disability/genetics* ; Mutation ; Whole Exome Sequencing

Age-related hearing loss (AHL) is one of the most common sensory disorders among elderly persons. The inwardly rectifying potassium channel 5.1 (Kir5.1) plays a vital role in regulating cochlear K(+) circulation which is necessary for normal hearing. The distribution of Kir5.1 in C57BL/6J mice cochleae, and the relationship between the expression of Kir5.1 and the etiology of AHL were investigated. Forty C57BL/6J mice were randomly divided into four groups at 4, 12, 24 and 52 weeks of age respectively. The location of Kir5.1 was detected by immunofluorescence technique. The mRNA and protein expression of Kir5.1 was evaluated in mice cochleae using real-time polymerase-chain reactions (RT-PCR) and Western blotting respectively. Kir5.1 was detected in the type II and IV fibrocytes of the spiral ligament in the cochlear lateral wall of C57BL/6J mice. The expression levels of Kir5.1 mRNA and protein in the cochleae of aging C57BL/6J mice were down-regulated. It was suggested that the age-related decreased expression of Kir5.1 in the lateral wall of C57BL/6J mice was associated with hearing loss. Our results indicated that Kir5.1 may play an important role in the pathogenesis of AHL.
Aging ; genetics ; metabolism ; Animals ; Cations, Monovalent ; Fluorescent Antibody Technique ; Gene Expression Regulation ; Ion Transport ; Mice ; Mice, Inbred C57BL ; Microtomy ; Potassium ; metabolism ; Potassium Channels, Inwardly Rectifying ; genetics ; metabolism ; Presbycusis ; genetics ; metabolism ; physiopathology ; RNA, Messenger ; genetics ; metabolism ; Spiral Ligament of Cochlea ; metabolism ; physiopathology ; ultrastructure

OBJECTIVETo investigate the prevalence of KCNJ5 gene missense mutations and their role in patients with unilateral adrenal hyperplasia (UAH).

METHODSFourteen UAH tissues were collected through surgical resection, and all the tissues were confirmed by pathology. Peripheral blood samples of the same patients were collected as control. The coding regions of the KCNJ5 were detected by direct DNA sequencing. Protein structure and function were predicted with specific software.

RESULTSThree missense mutations were detected among the 14 patients with UAH, which included c.451G>C/A (p.G151R) (2/14), c.503T>G (p.L168R) (1/14), c.830T>A (p.S209T) (9/14). Among these, c.830T>A is a newly identified somatic mutation. Protein structure prediction showed that S209T lied in the second transmembrane domain, a conservation region of KCNJ5. S209 was also the phosphorylation site of PKC that is located in intracellular area.

CONCLUSIONMissense mutations of KCNJ5 gene may be associated with UAH. Protein structure prediction has suggested that KCNJ5 mutations may be associated with UAH.

Adrenal Hyperplasia, Congenital ; genetics ; Adult ; Aged ; Amino Acid Sequence ; Female ; G Protein-Coupled Inwardly-Rectifying Potassium Channels ; genetics ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; Mutation, Missense ; Sequence Analysis, DNA

Inwardly rectifying potassium (Kir) channels exhibit an asymmetrical conductance at hyperpolarization (high conductance) compared to depolarization (low conductance). The KCNJ10 gene which encodes an inwardly rectifying K+ channel Kir4.1 subunit plays an essential role in the inner ear and hearing. Mutations or deficiency of KCNJ10 can cause hearing loss with epilepsy, ataxia, sensorineural deafness, and renal tubulopathy (EAST) or SeSAME (seizures, sensorineural deafness, ataxia, mental retardation, and electrolyte imbalance) syndromes. In this review, we mainly focus on the expression and function of Kir4.1 channels in the inner ear and mutation-induced EAST/SeSAME syndromes to provide insight for understanding the pathogenesis of deafness induced by KCNJ10 deficiency.
Deafness ; genetics ; metabolism ; Ear, Inner ; metabolism ; Hearing Loss, Sensorineural ; genetics ; metabolism ; Humans ; Intellectual Disability ; genetics ; metabolism ; Mutation ; Potassium Channels, Inwardly Rectifying ; genetics ; metabolism ; Seizures ; genetics ; metabolism

OBJECTIVETo assess the association between polymorphisms of rs3740835(C/A) and rs2604204(A/C) in KCNJ5 gene with the susceptibility to unilateral and bilateral primary aldosteronism (PA).

METHODSA total of 1043 subjects were studied, which included 83 unilateral PA patients,142 bilateral PA patients and 818 essential hypertensive(EH) patients. The polymorphism of KCNJ5 gene at rs3740835(C/A) and rs2604204(A/C) position were analyzed with a TaqMan genotyping technique.

RESULTSFrequencies of A allele and AA+AC genotype at rs3740835(C/A) in unilateral PA group were significantly higher than EH group (P < 0.05). However, the above frequencies did not show a statistical significance between bilateral PA group and EH group (P > 0.05). No statistical difference was detected in the distribution of alleles or genotypes at rs2604204 (A/C) between unilateral PA and EH group or between bilateral PA and EH group. Haplotypic frequencies of C-A and A-A in unilateral PA group were significantly higher and lower than EH group, respectively. However, there was no statistical difference in the haplotype distribution between bilateral PA and EH groups.

CONCLUSIONRs3740835(C/A) polymorphism may be associated with unilateral PA but not with bilateral PA. rs2604204(A/C) polymorphism is not associated with either unilateral or bilateral PA. Haplotype C-A and A-A may respectively be susceptibility factor and protective factor for unilateral PA. No haplotype has been found to associate with bilateral PA.

Adult ; Female ; G Protein-Coupled Inwardly-Rectifying Potassium Channels ; genetics ; Haplotypes ; Humans ; Hyperaldosteronism ; genetics ; Male ; Middle Aged ; Polymorphism, Genetic

OBJECTIVETo assess the association of polymorphisms of G protein-coupled inwardly-rectifying potassium channels 4 (GIRK4) gene with essential hypertension in ethnic Uygurs from southern Xinjiang.

METHODSA total of 1194 (461 males and 733 females) Uygur residents aged 30 to 70 and with a body mass index (BMI) over 18.5 kg/m(2) were selected from Hetian region. All of the subjects have received questionnaire survey, physical examination, biochemical analysis and blood pressure measurement. They were divided into hypertensive group and normotensive group. Genotyping by the TaqMan polymerase chain reaction method was performed for 4 common single nucleotide polymorphisms (rs4937391, rs2604204, rs6590357 and rs1122149), and a case-control study was carried out.

RESULTSGenotype distributions of rs4937391, rs2604204, rs6590357 and rs1122149 in both groups were in Hardy-Weinberg equilibrium (P> 0.05). The average systolic blood pressure of CC genotype of rs11221497 single nucleotide polymorphism (SNP)[(132.69± 26.9) mmHg)] was higher than the CG genotype [(127.4± 22.7) mmHg] and GG genotype [(121.1± 26.3) mmHg]. There has a significantly difference in average systolic and diastolic blood pressures between CC and GG genotypes (P< 0.05). A case-control association analysis revealed that the rs11221497 SNP was in association with essential hypertension with the dominant model [P< 0.05, OR= 0.67 (0.49-0.93)]. Haplotype analysis indicated that H6(C-G-C-G) was significantly more common in normotensive group than hypertensive group (P= 0.001).

CONCLUSIONThe rs11221497 SNP of the GIRK4 gene is associated with essential hypertension in ethnic Uygur population in Xinjiang.

Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; Essential Hypertension ; Female ; G Protein-Coupled Inwardly-Rectifying Potassium Channels ; genetics ; Genetic Predisposition to Disease ; Humans ; Hypertension ; complications ; genetics ; Male ; Obesity ; complications ; genetics ; Polymorphism, Single Nucleotide

OBJECTIVEE23K polymorphism in KCNJ11 gene is associated with cardiovascular disease and diabetes. In order to explore the mechanism of E23K correlation to related diseases, the effect of E23K polymorphism in KCNJ11 gene on membrane current was investigated.

METHODSThe exon of KCNJ11 was obtained by PCR amplification and the G-->A mutation was completed by overlap extension PCR. The sequences of KCNJ11 exon contained 23E or 23K was inserted into pcDNA3.1/CT-GFP vector respectively. The recombinant plasmid, pcDNA3.1-KCNJ11(E) and pcDNA3.1-KCNJ11(K), were transfected into HEK293T cells by lipofectamine and the membrane current density was determined by whole-cell patch clamp technique.

RESULTS1,173 bp sequences of KCNJ11 gene's exon were amplified by PCR and the recombinant expression plasmid, pcDNA3.1-KCNJ11(E) and pcDNA3.1-KCNJ11(K), were constructed successful. Positive and negative currents were detected in HEK293T cells transfected with difference plasmid by whole-cell patch clamp technique. Results showed that the reversed voltage was 50mV. The current in HEK293T cells with pcDNA3.1-KCNJ11(E) was significantly greater than that with pcDNA3.1-KCNJ11(K) (P < 0.05, n = 10).

CONCLUSIONThe polymorphism of E23K in exon of KCNJ11 gene changed the membrane currents in HEK293T cells. It could be an experiment support for the possible mechanism between the locus and related diseases.

Exons ; HEK293 Cells ; Humans ; Membrane Potentials ; Patch-Clamp Techniques ; Polymorphism, Genetic ; Potassium Channels, Inwardly Rectifying ; genetics

OBJECTIVETo investigate the relationship between the G protein-gated inward rectifier K+ channel subunit 4 (GIRK4) gene polymorphism and the dyslipidemia among Uyghur residents in Xinjiang.

METHODSThe polymorphisms of rs2604204, rs4937391, rs6590357, and rs11221497 among the Uyghur residents were genotyped using Taqman polymerase chain reaction (PCR). Lipid levels were measured by conventional methods and were analyzed.

RESULTSIn the less-than-50-years population, the genotype distributions of the rs6590357 was statistically significant different in subjects with or without abnormal triglycerides (P=0.005). Aslo, the the genotype distributions of the rs11221497 also significantly differed in subjects with normal compared or abnormal TG (P=0.011). Logistic regression analysis suggested that rs6590357 still had positive association with TG abnormalities in subjects under 50 years (P=0.014). rs11221497 also had positive association with TC abnormalities. The TG levels of CT+TT genotypes were significantly higher than the CC group (P=0.006). Haplotype analysis found that the differences of H3 haplotype frequencies between the TG abnormal and normal groups were statistically significant (P=0.007).

CONCLUSIONThe polymorphisms of rs11221497 and rs6590357 of GIRK4 gene may play a role in the development of dyslipidemia in Uygur population.

China ; epidemiology ; Dyslipidemias ; epidemiology ; metabolism ; Genotype ; Humans ; Polymerase Chain Reaction ; Polymorphism, Single Nucleotide ; Potassium Channels, Inwardly Rectifying ; genetics ; Triglycerides