A de novo Mutation (p.Gln277X) of Cyclin D2 is Responsible for a Child with Megalencephaly-Polymicrogyria-Polydactyly-Hydrocephalus Syndrome

Megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome (MPPH), a type of overgrowth syndrome, is characterized by progressive megalencephaly, cortical brain malformations, and distal limb anomalies. Previous studies have revealed that the overactivity of the phosphatidylinositol 3-kinase-Protein kinase B pathway and the increased cyclin D2 (CCND2) expression were the main factors contributing to this disease. Here, we present the case of a patient who exhibited megalencephaly, polymicrogyria, abnormal neuronal migration, and developmental delay. Serum tandem mass spectrometry and chromosome examination did not detect any metabolic abnormalities or copy number variants. However, whole-exome sequencing and Sanger sequencing revealed a de novo nonsense mutation (NM_001759.3: c.829C>T; p.Gln277X) in the CCND2 gene of the patient. Bioinformatics analysis predicted that this mutation may disrupt the structure and surface charge of the CCND2 protein. This disruption could potentially prevent polyubiquitination of CCND2, leading to its resistance against degradation. Consequently, this could drive cell division and growth by altering the activity of key cell cycle regulatory nodes, ultimately contributing to the development of MPPH. This study not only presents a new case of MPPH and expands the mutation spectrum of CCND2 but also enhances our understanding of the mechanisms connecting CCND2 with overgrowth syndromes.

RTN3 deficiency exacerbates cisplatin-induced acute kidney injury through the disruption of mitochondrial stability

Reticulum 3 (RTN3) is an endoplasmic reticulum (ER) protein that has been reported to act in neurodegenerative diseases and lipid metabolism. However, the role of RTN3 in acute kidney injury (AKI) has not been explored. Here, we employed public datasets, patient data, and animal models to explore the role of RTN3 in AKI. The underlying mechanisms were studied in primary renal tubular epithelial cells and in the HK2 cell line. We found reduced expression of RTN3 in AKI patients, cisplatin-induced mice, and cisplatin-treated HK2 cells. RTN3-null mice exhibit more severe AKI symptoms and kidney fibrosis after cisplatin treatment. Mitochondrial dysfunction was also found in cells with RTN3 knockdown or knockout. A mechanistic study revealed that RTN3 can interact with HSPA9 in kidney cells. RTN3 deficiency may disrupt the RTN3-HSPA9-VDAC2 complex and affect MAMs during ER-mitochondrion contact, which further leads to mitochondrial dysfunction and exacerbates cisplatin-induced AKI. Our study indicated that RTN3 was important in the kidney and that a decrease in RTN3 in the kidney might be a risk factor for the aggravation of AKI.

Case report: Whole exome sequencing identified a novel mutation (p.Y301H) of MAF in a Chinese family with congenital cataracts

Background

Congenital cataracts stand as the primary cause of childhood blindness globally, characterized by clouding of the eye's lens at birth or shortly thereafter. Previous investigations have unveiled that a variant in the V-MAF avian musculoaponeurotic-fibrosarcoma oncogene homolog (MAF) gene can result in Ayme-Gripp syndrome and solitary cataract. Notably, MAF mutations have been infrequently reported in recent years.

Methods

In this investigation, we recruited a Chinese family with non-syndromic cataracts. Whole exome sequencing and Sanger sequencing were applied to scrutinize the genetic anomaly within the family.

Results

Through whole exome sequencing and subsequent data filtration, a new mutation (NM_005360, c.901T>C/p.Y301H) in the MAF gene was detected. Sanger sequencing validated the presence of this mutation in another affected individual. The p.Y301H mutation, situated in an evolutionarily preserved locus, was not detected in our 200 local control cohorts and various public databases. Additionally, multiple bioinformatic programs predicted that the mutation was deleterious and disrupted the bindings between MAF and its targets.

Conclusion

Hence, we have documented a new MAF mutation within a Chinese family exhibiting isolated congenital cataracts. Our study has the potential to broaden the spectrum of MAF mutations, offering insights into the mechanisms underlying cataract formation and facilitating genetic counseling and early diagnosis for congenital cataract patients.

A compound heterozygous mutation of ERCC8 is responsible for a family with Cockayne syndrome

BACKGROUND

Cockayne syndrome is an inherited heterogeneous defect in transcription-coupled DNA repair (TCR) cause severe clinical syndromes, which may affect the nervous system development of infants and even lead to premature death in some cases. ERCC8 diverse critical roles in the nucleotide excision repair (NER) complex, which is one of the disease-causing genes of Cockayne syndrome.

METHODS AND RESULTS

The mutation of ERCC8 in the patient was identified and validated using WES and Sanger sequencing. Specifically, a compound heterozygous mutation (c.454_460dupGTCTCCA p. T154Sfs*13 and c.755_759delGTTTT p.C252Yfs*3) of ERCC8 (CSA) was found, which could potentially be the genetic cause of Cockayne syndrome in the proband.

CONCLUSION

In this study, we identified a novel heterozygous mutation of ERCC8 in a Chinese family with Cockayne syndrome, which enlarging the genetic spectrum of the disease.

Gravity-based focusing and size-dependent separation of metal microparticles in lubricating oil

The separation of wear microparticles in lubricating oil is crucial for improving the accuracy and throughput of the subsequent detection. However, there are few kinds of research on the separation of high-density metallic microparticles in high-viscosity lubricating oil. In this paper, a passive method for separating the metallic microparticles in oil is proposed. Gravity sedimentation was adopted to realize three-dimensional (3D) focusing of the particle by using an inclined capillary. The gravity-based 3D focusing made the sheath flow no longer responsible for the particle focusing and effectively reduced the sheath flow. Then, the separation of different-sized metallic microparticles was achieved in a horizontal channel with the aid of a sheath flow based on the different driving forces. The present method solved the problem of nonsynchronous separation of the particle in comparison to the traditional methods. This device has a simple structure with high separation efficiency, and it is easy to integrate with the detection channel. The influence of numerous parameters on the gravity-based focusing and separation was systematically studied by the numerical simulation and the experiment. The design criteria were established, which is useful in designing and employing the device, expanding its application to other non-neutral buoyancy particle separation cases, and opening up more prospects for microfluidic technology.

A novel mutation of CTC1 leads to telomere shortening in a chinese family with interstitial lung disease

Interstitial lung diseases (ILDs), or diffuse pulmonary lung disease, are a subset of lung diseases that primarily affect lung alveoli and the space around interstitial tissue and bronchioles. It clinically manifests as progressive dyspnea, and patients often exhibit a varied decrease in pulmonary diffusion function. Recently, variants in telomere biology-related genes have been identified as genetic lesions of ILDs. Here, we enrolled 82 patients with interstitial pneumonia from 2017 to 2021 in our hospital to explore the candidate gene mutations of these patients via whole-exome sequencing. After data filtering, a novel heterozygous mutation (NM_025099: p.Gly131Arg) of CTC1 was identified in two affected family members. As a component of CST (CTC1-STN1-TEN1) complex, CTC1 is responsible for maintaining telomeric structure integrity and has also been identified as a candidate gene for IPF, a special kind of chronic ILD with insidious onset. Simultaneously, real-time PCR revealed that two affected family members presented with short telomere lengths, which further confirmed the effect of the mutation in the CTC1 gene. Our study not only expanded the mutation spectrum of CTC1 and provided epidemiological data on ILDs caused by CTC1 mutations but also further confirmed the relationship between heterozygous mutations in CTC1 and ILDs, which may further contribute to understanding the mechanisms underlying ILDs.

Case report: A novel WASHC5 variant altering mRNA splicing causes spastic paraplegia in a patient

Background: Hereditary spastic paraplegia (HSP) is a progressive upper-motor neurodegenerative disease. Mutations in the WASHC5 gene are associated with autosomal dominant HSP, spastic paraplegia 8 (SPG8). However, due to the small number of reported cases, the exact mechanism remains unclear. Method: We report a Chinese family with HSP. The proband was referred to our hospital due to restless leg syndrome and insomnia. The preliminary clinical diagnosis of the proband was spastic paraplegia. Whole-exome sequencing (WES) and RNA splicing analysis were conducted to evaluate the genetic cause of the disease in this family. Results: A novel splice-altering variant (c.712-2A>G) in the WASHC5 gene was detected and further verified by RNA splicing analysis and Sanger sequencing. Real-time qPCR analysis showed that the expression of genes involved in the Wiskott-Aldrich syndrome protein and SCAR homolog (WASH) complex and endosomal and lysosomal systems was altered due to this variant. Conclusion: A novel heterozygous splice-altering variant (c.712-2A>G) in the WASHC5 gene was detected in a Chinese family with HSP. Our study provided data for genetic counseling to this family and offered evidence that this splicing variant in the WASHC5 gene is significant in causing HSP.

Case report: Identification of a recurrent pathogenic DHDDS mutation in Chinese family with epilepsy, intellectual disability and myoclonus

Background: Heterozygous mutations in the dehydrodolichol diphosphate synthase (DHDDS) gene are one of the causes generating developmental and epileptic encephalopathies. So far, only eleven mutations in the DHDDS gene have been identified. The mutation spectrum of the DHDDS gene in the Chinese population remains unclear. Methods: In this study, we enrolled a Chinese family with myoclonus and/or epilepsy and intellectual disability. The epilepsy and myoclonic tremor were improved after deep brain stimulation (DBS) of the subthalamic nucleus (STN) treatment. Whole exome sequencing and Sanger sequencing were employed to explore the genetic variations of the family. Results: Subsequent to data filtering, we identified a recurrent pathogenic mutation (NM_001243564.1, c.113G>A/p.R38H) in the DHDDS gene in the proband. Sanger sequencing further validated that the presence of the mutation in his affected mother but absent in the health family members. Further bioinformatics analysis revealed that this mutation (p.R38H), located in an evolutionarily conserved region of DHDDS, was predicted to be deleterious. Discussion: In this report, we present the first case of intractable epilepsy and/or myoclonus caused by p.R38H mutation of the DHDDS gene in the Chinese population. Furthermore, this study represents the third report of autosomal dominant familial inheritance of DHDDS mutation worldwide.

[Mechanism of piRNA in bisphenol A-promoted invasion and migration of prostate cancer cells]

Objective: To investigate the regulatory mechanisms of piwi-interacting RNA (piRNA) in bisphenol A (BPA)-induced prostate cancer cell invasion and migration. Methods: The Cancer Genome Atlas (TCGA) data was used to analyze and screen for piRNAs with significantly increased expression in prostate cancer tissues. PC-3 cells were treated with different concentrations of BPA for 12, 24, and 48 h, respectively, and the 20% inhibitory concentration (IC20) was measured using a CCK-8 assay. The expression levels of piRNAs before and after BPA treatment were determined by reverse transcription-quantitative PCR. Target genes regulated by BPA and associated with prostate cancer were screened in the Comparative Toxicogenomics Database (CTD). Dual-luciferase reporter gene assay was performed to verify the relationship between piRNA and target genes, and the expression change of the piRNA target gene was detected by Western blotting. Cell migration and invasion assays were used to determine the effects of piRNA on the malignant phenotype of prostate cancer cells. Results: After treatment of PC-3 cells with 160 μmol/L BPA, the expression of piR-sno48 was most significantly increased (P<0.05). Transfection of piR-sno48 antagomir resulted in decreased expression of endogenous piR-sno48 and a significant increase in the expression of its target gene GSTP1 (P<0.05). However, the expression of GSTP1 did not change significantly in BPA-treated PC-3 cells after transfection with piR-sno48 antagomir (P>0.05). The dual-luciferase reporter gene confirmed that piR-sno48 inhibited the expression of GSTP1 by forming an inversely complementary sequence with the 3'-UTR of GSTP1. The Transwell assay results showed that treatment with BPA significantly increased the invasion and migration ability of prostate cancer cells (P<0.01), whereas piR-sno48 antagonists significantly inhibited the effects above (P<0.01). Conclusion: BPA promotes the invasion and migration of prostate cancer cells by upregulating the expression of piR-sno48 and suppressing the expression of GSTP1. Interfering with the expression of endogenous piR-sno48 may inhibit the malignant phenotype of prostate cancer cells caused by BPA.

Case report: A novel mutation of RecQ-like helicase 5 in a Chinese family with early myocardial infarction, coronary artery disease, and stroke hemiplegia

Background: Myocardial infarction (MI) is a type of severe coronary artery disease (CAD) that can lead to heart failure and sudden cardiac death. The prevalence of heart failure globally is estimated at 1%-2%, of which ∼60% of cases are the consequence of MI as the primary cause. At present, several disease-causing genes have been identified that may be responsible for MI, such as autophagy-related 16-like 1 (ATG16L1) and RecQ-like helicase 5 (RECQL5). Methods: In this study, we enrolled a Chinese family with MI, CAD, and stroke hemiplegia. Whole-exome sequencing was applied to analyze the genetic lesion of the proband. Sanger sequencing was used to validate the candidate mutation in five family members and 200 local control cohorts. Results: After data filtering, we detected a novel mutation (NM_004259: c.1247T>C/p.I416T) of RECQL5 in the proband. Sanger sequencing further validated that the novel mutation was existent in the affected individuals, including the proband's younger sister and her mother, and absent in the other healthy family members and 200 local control cohorts. Furthermore, bioinformatics analysis confirmed that the novel mutation, located in a highly evolutionarily conserved site, was predicted to be deleterious and may change the hydrophobic surface area and aliphatic index of RECQL5. Conclusion: Here, we report the second mutation (NM_004259: c.1247T>C/p.I416T) of RECQL5 underlying MI and CAD by whole-exome sequencing. Our study expanded the spectrum of RECQL5 mutations and contributed to genetic diagnosis and counseling of MI and CAD.

Efficient Focusing of Aerosol Particles in the Microchannel under Reverse External Force: A Numerical Simulation Study

Focusing aerosol particles efficiently is of great significance for high-precision aerosol jet printing and detection of the airborne target. A new method was proposed herein to achieve the efficient focusing of aerosol particles in the microchannel by using a reverse external force. Considering the slip at the interface between the gas and the aerosol particle, a numerical model of the particle movement in the microchannel was established and simulations were conducted on the gas-particle two-phase flow in the microchannel under the effect of the reverse external force. The results showed that a suitable reverse external force in a similar order of magnitude to the Stokes force can dramatically increase the velocity difference between the particle and the gas, which significantly enhances the Saffman lift force exerted on the aerosol particle. Eventually, the aerosol particle can be efficiently focused at the center of the microchannel in a short channel length. In addition, the influence of the channel geometry, the magnitude, and the direction of the external force on the particle focusing was also studied. This work is of great significance for the precise detection of aerosol particles and the design of nozzles for aerosol jet printing.

The first case report of CODAS syndrome in Chinese population caused by two LONP1 pathogenic mutations

Background: CODAS syndrome (MIM 600373) is a multi-system developmental disorder characterized by cerebral, ocular, dental, auricular, and skeletal anomalies. CODAS syndrome is rare in the world and no cases have been reported in Chinese population so far. Mutations in the LONP1 gene can contribute to CODAS syndrome, while the underlying molecular mechanisms requires further investigation. Method: We described a Chinese boy who has suffered from cognition impairment, cataracts, caries, abnormal auricle and skeletal anomalies since birth. The patient's parents are non-consanguineous and healthy. Whole-exome sequencing (WES) was employed to explore the genetic entity of this family. Results: A compound heterozygous missense mutation (NM_004793: c.2009C>T/p.A670V and c.2014C>T/p.R672C) of LONP1 was identified in the patient. Considering the clinical phenotypes and genetic results, the patient was diagnosed as CODAS syndrome. Conclusion: Here we reported the first case with CODAS syndrome in Chinese population. WES identified a compound heterozygous missense mutation of LONP1 gene in the patients. Our study not only provided data for genetic counseling and clinical diagnosis to this family, but also expanded the clinical spectrum of LONP1-related CODAS syndrome.

Case report: Whole-exome sequencing identifies a novel DES mutation (p. E434K) in a Chinese family with cardiomyopathy and sudden cardiac death

Background

Desmin is an intermediate filament protein that plays a critical role in the stabilization of the sarcomeres and cell contacts in the cardiac intercalated disk. Mutated DES gene can cause hereditary cardiomyopathy with heterogeneous phenotypes, while the underlying molecular mechanisms requires further investigation.

Methods

We described a Chinese family present with cardiomyopathy and sudden cardiac death (SCD). Whole-exome sequencing (WES) and bioinformatics strategies were employed to explore the genetic entity of this family.

Results

An unknown heterozygote missense variant (c.1300G > A; p. E434K) of DES gene was identified. The mutation cosegregates in this family. The mutation was predicted as pathogenic and was absent in our 200 healthy controls.

Conclusion

We identified a novel DES mutation (p. E434K) in a Chinese family with cardiomyopathy and SCD. Our study not only provided a new case for the study of the relationship between DES mutations and hereditary cardiomyopathy but also broadened the spectrum of DES mutations.

Loss of RTN3 phenocopies chronic kidney disease and results in activation of the IGF2-JAK2 pathway in proximal tubular epithelial cells

Reticulon 3 (RTN3) is an endoplasmic reticulum protein that has previously been shown to play roles in neurodegenerative diseases, but little is known about its function in the kidneys. The aim of the present study was to clarify the roles of RTN3 in chronic kidney disease (CKD) and kidney fibrosis. In this study, RTN3 levels were measured in kidney tissues from healthy controls and CKD or kidney fibrosis patients. An RTN3-null mouse model was generated to explore the pathophysiological roles of RTN3 in the kidneys. The underlying mechanisms were studied in primary proximal tubular epithelial cells and HEK293 cells in vitro. The results showed that (1) a reduction in RTN3 in mice induces CKD and kidney fibrosis; (2) decreased RTN3 expression is found in patients with CKD; (3) RTN3 plays critical roles in regulating collagen biosynthesis and mitochondrial function; and (4) mechanistically, RTN3 regulates these phenotypes by interacting with GC-Rich Promoter Binding Protein 1 (GPBP1), which activates the IGF2-JAK2-STAT3 pathway. Our study indicates that RTN3 might play crucial roles in CKD and kidney fibrosis and that a reduction in RTN3 in the kidneys might be a risk factor for CKD and kidney fibrosis.

A protein (RTN3) known to be involved in neurodegenerative diseases may play a causative role in kidney fibrosis or scarring, and chronic kidney disease (CKD). An estimated 20% of CKD cases may have genetic causes and identifying the genes involved may help find better treatments. Ri-Qiang Yan at the University of Connecticut Health, Farmington, USA, and Rong Xian at Central South University, China, noticed that mice in which the gene coding for RTN3 was inactivated had kidney fibrosis. The researchers showed that RTN3 levels were also lower in kidney tissues of patients with CKD than in healthy individuals and that RTN3 levels were inversely proportional to disease progression. Further investigation showed that decreased RTN3 caused extra collagen deposition and misshapen mitochondria, the cellular powerhouses, in the kidney. These results identify a potential novel risk factor for CKD.

GLIS Family Zinc Finger 1 was First Linked With Preaxial Polydactyly I in Humans by Stepwise Genetic Analysis

Background: Preaxial polydactyly (PPD) is one of the most common developmental malformations, with a prevalence of 0.8–1.4% in Asians. PPD is divided into four types, PPD I–IV, and PPD I is the most frequent type. Only six loci (GLI1, GLI3, STKLD1, ZRS, pre-ZRS, and a deletion located 240 kb from SHH) have been identified in non-syndromic PPD cases. However, pathogenesis of most PPD patients has never been investigated. This study aimed to understand the genetic mechanisms involved in the etiology of PPD I in a family with multiple affected members.

Methods: We recruited a PPD I family (PPD001) and used stepwise genetic analysis to determine the genetic etiology. In addition, for functional validation of the identified GLIS1 variant, in vitro studies were conducted. GLIS1 variants were further screened in additional 155 PPD cases.

Results: We identified a GLIS1 variant (NM_147193: c.1061G > A, p.R354H) in the PPD001 family. In vitro studies showed that this variant decreased the nuclear translocation of GLIS1 and resulted in increased cell viability and migration. RNA sequencing revealed abnormal TBX4 and SFRP2 expression in 293T cells transfected with mutant GLIS1. Additionally, we identified a GLIS1 variant (c.664G > A, p.D222N) in another PPD case.

Conclusion: We identified two GLIS1 variants in PPD I patients and first linked GLIS1 with PPD I. Our findings contributed to future molecular and clinical diagnosis of PPD and deepened our knowledge of this disease.

Case Report: Congenital Brain Dysplasia, Developmental Delay and Intellectual Disability in a Patient With a 7q35-7q36.3 Deletion

7q terminal deletion syndrome is a rare condition presenting with multiple congenital malformations, including abnormal brain and facial structures, developmental delay, intellectual disability, abnormal limbs, and sacral anomalies. At least 40 OMIM genes located in the 7q34-7q36.3 region act as candidate genes for these phenotypes, of which SHH, EN2, KCNH2, RHEB, HLXB9, EZH2, MNX1 and LIMR1 may be the most important. In this study, we discuss the case of a 2.5-year-old male patient with multiple malformations, congenital brain dysplasia, developmental delay, and intellectual disability. A high-resolution genome-wide single nucleotide polymorphism array and real-time polymerase chain reaction were performed to detect genetic lesions. A de novo 9.4 Mb deletion in chromosome region 7q35-7q36.3 (chr7:147,493,985-156,774,460) was found. This chromosome region contains 68 genes, some of which are candidate genes for each phenotype. To the best of our knowledge, this is a rare case report of 7q terminal deletion syndrome in a Chinese patient. Our study identifies a rare phenotype in terms of brain structure abnormalities and cerebellar sulcus widening in patients with deletion in 7q35-7q36.3.

Case Report: A Novel CACNA1S Mutation Associated With Hypokalemic Periodic Paralysis in a Chinese Family

Hypokalemic periodic paralysis (HypoPP) is a rare autosomal dominant disorder characterized by episodic flaccid paralysis with concomitant hypokalemia. More than half of patients were associated with mutations in CACNA1S that encodes the alpha-1-subunit of the skeletal muscle L-type voltage-dependent calcium channel. Mutations in CACNA1S may alter the structure of CACNA1S and affect the functions of calcium channels, which damages Ca²⁺-mediated excitation-contraction coupling. In this research, we identified and described a Chinese HypoPP patient with a novel frameshift mutation in CACNA1S [NM_000069.2: c.1364delA (p.Asn455fs)] by targeted sequencing. This study would expand the spectrum of CACNA1S mutations, further our understanding of HypoPP, and provided a new perspective for selecting effective treatments.

A novel POF1B variant in a Chinese patient is associated with premature ovarian failure

A novel mutation of POF1B was identified in a patient with premature ovarian failure.

[Study of influence of birth weight on risk of chronic diseases and blood uric acid in adulthood]

Objective: To understand the influence of birth weight on the risk of chronic diseases, such as hypertension and diabetes, and the relationship between birth weight and serum uric acid in adulthood. Methods: According to the Chinese Adult Chronic Disease and Nutrition Surveillance Program, a total of 1 131 residents aged 18 years and above were enrolled from Hexi, Nankai, Hongqiao, Wuqing, Jinnan, Baodi and Jizhou districts of Tianjin. The data of birth weight and blood pressure of the residents were collected, and fasting venous blood samples were collected from them to detect uric acid, blood glucose and blood lipids levels. The distribution of birth weight of the surveyed population was described, and the relationship between birth weight and chronic diseases, such as hypertension and diabetes, and the blood uric acid level in adulthood were analyzed. Results: The average birth weight of the surveyed population in Tianjin was 3.37 kg, which was higher in males than in females. No matter overweight/obesity, hypertension or diabetes, the prevalence rate of normal birth weight was the lowest in adulthood. After univariate logistic regression analysis and adjusting for age, sex, smoking and drinking status, it was found that compared with normal birth weight, low birth weight had a stronger correlation with diabetes (OR=2.91,95%CI:1.46-5.76) and dyslipidemia (OR=1.79,95%CI:1.01-3.19) in adulthood. Macrosomia was strongly associated with overweight/obesity in adulthood (OR=1.47, 95%CI:1.08-2.01). There was no significant difference in serum uric acid level among the residents with different birth weights. Conclusions: The low birth weight of the surveyed population in Tianjin was closely related to the risk of diabetes and dyslipidemia in adulthood, and the macrosomia was closely related to the risk of overweight/obesity in adulthood.

Inhibitory effects of lactoferrin on pulmonary inflammatory processes induced by lipopolysaccharide by modulating the TLR4-related pathway

This study tested the ability of lactoferrin to modulate pulmonary inflammation. To construct in vitro and in vivo inflammatory lung models, cells from the human lung adenocarcinoma cell line (A549) were exposed to lipopolysaccharide (LPS, 1 µg/mL), and mice (CD-1) were intratracheally administered LPS [10 mg/kg of body weight (BW), tracheal lumen injection], respectively. The A549 cells were preincubated with lactoferrin (10 mg/mL), and the mice were intraperitoneally injected with lactoferrin (100 mg/kg of BW), followed by LPS treatment. The concentrations of proinflammatory cytokines (IL-1β and TNF-α) in culture medium of A549 cells and in bronchoalveolar lavage fluid of the mice were determined using enzyme-linked immunosorbent assays. The toll-like receptor 4-related pathway (TLR4/MyD88/IRAK1/TRAF6/NFκB) was determined at gene and protein expression levels in A549 cells and mouse lung tissue. Results showed that LPS treatment significantly elevated the concentrations of IL-1β and TNF-α in the A549 cell culture medium and in bronchoalveolar lavage fluid of the mice; it also elevated both the mRNA and protein expressions of TLR4 and the TLR4 downstream factors in A549 cells and mouse lung tissue. Nevertheless, lactoferrin apparently depressed the releases of IL-1β and TNF-α from A549 cells and lung tissues stimulated by LPS, and significantly suppressed the TLR4 signaling pathway. Lactoferrin also promoted the enhancement of miR-146a expression in A549 cells and mouse lung tissue. Moreover, 100°C heating for 3 min caused total loss of the previously listed bioactivity of lactoferrin. Collectively, we proved that lactoferrin intervened in LPS-induced inflammation in the pulmonary cell model and in the mouse model, through inhibiting the TLR4-related pathway.

Case Report: A Homozygous Mutation (p.Y62X) of Phospholipase D3 May Lead to a New Leukoencephalopathy Syndrome

Leukodystrophies are a heterogeneous group of inherited disorders with highly variable clinical manifestations and pathogenetic backgrounds. At present, variants in more than 20 genes have been described and may be responsible for different types of leukodystrophies. Members of the phospholipase D family of enzymes catalyze the hydrolysis of membrane phospholipids. Meanwhile, phospholipase D3 (PLD3) has also been found to exhibit single stranded DNA (ssDNA) acid 5' exonuclease activity. Variants in phospholipase D3 (PLD3) may increase the risk of Alzheimer's disease and spinocerebellar ataxia, but this hypothesis has not been fully confirmed. In this study, we identified a novel homozygous mutation (NM_012268.3: c.186C>G/ p.Y62X) of PLD3 in a consanguineous family with white matter lesions, hearing and vision loss, and kidney disease by whole exome sequencing. Real-time PCR revealed that the novel mutation may lead to non-sense-mediated messenger RNA (mRNA) decay. This may be the first case report on the homozygous mutation of PLD3 in patients worldwide. Our studies indicated that homozygous mutation of PLD3 may result in a novel leukoencephalopathy syndrome with white matter lesions, hearing and vision loss, and kidney disease.

[Study on the diet balance index and its relationship with blood uric acid of smoking adults in Tianjin]

Objective: Diet balance index (DBI_16) was used to evaluate the dietary status of smoking adults in Tianjin, and the relationship between DBI_16 and serum uric acid was analyzed. Methods: A total of 1 478 inhabitants aged 18 and above were enrolled. The dietary status was obtained with a 3-day dietary recall and condiment weighing method. And their fasting venous blood was collected to detect uric acid. Food intake and DBI_16 scores of smokers and non-smokers were described, and the relationship among smoking, diet quality distance (DQD-DBI), and serum uric acid was analyzed. Results: The intake of vegetables, fruits, and milk of smokers in Tianjin was lower than while the salt, oil, cereals, and aquatic products were higher than that of non-smokers. The DBI_16 scores of vegetables and fruits, food types, milk, and beans of smokers were lower than those of non-smokers in Tianjin, and the scores of pure energy foods and condiments were higher than those of the non-smokers. The DQD-DBI, high bound score and low bound score of smokers in Tianjin were 42.0, 14.0, and 29.0 respectively, which were all higher than those of non-smokers. The main problems appeared as moderately inadequate intake (accounting for 67.0%), low, excessive intake (accounting for 70.9%), and moderate imbalance of intake (accounting for 67.2%). The serum uric acid of smokers was higher than in the non-smokers, and there the same result appeared under the conditions of "not suitable" in DQD-DBI. Conclusions: In Tianjin, the dietary imbalance was more evident in smokers than the non-smokers, and the serum uric acid was significantly higher than the non-smokers. Strategies as strengthening the nutrition education and intervention targeted for smokers were in urgent need.

Identification of a novel mutation in the C6 gene of a Han Chinese C6SD child with meningococcal disease

Deficiency of the sixth complement component (C6D) is a genetic disease associated with increased susceptibility to Neisseria meningitides infection. Individuals with C6D usually present with recurrent meningococcal disease (MD). According to the patients' C6 levels, C6D is divided into complete genetic deficiency of C6 and subtotal deficiency of C6 (C6SD). The present study reported on a Han Chinese pediatric patient with MD, in whom further investigation revealed a C6SD genetic lesion. A heterozygote nonsense mutation (c.1062C>G/p.Y354*) in the C6 gene was identified by Sanger sequencing. The mutation alters the tyrosine codon at position 354 to a termination codon and results in a truncated protein. In conclusion, the genetic lesion of a pediatric patient with C6SD who was diagnosed due to having MD was investigated and a novel pathogenic mutation in the C6 gene was identified. The study confirmed the clinical diagnosis for this patient with C6SD and also expanded the spectrum of C6 mutations.

Efficient microfluidic enrichment of nano-/submicroparticle in viscoelastic fluid

The enrichment and focusing of the nano-/submicroparticle (e.g., 150-1000 nm microvesicle shed from the plasma membrane) in the viscoelastic fluid has great potentials in the biomedical and clinical applications such as the disease diagnosis and the prognostic test for liquid biopsy. However, due to the small size and the resulting weak hydrodynamic force, the efficient manipulation of the nano-/submicroparticle by the passive viscoelastic microfluidic technology remains a major challenge. For instance, a typically long channel length is often required to achieve the focusing or the separation of the nano-/submicroparticle, which makes it difficult to be integrated in small chip area. In this work, a microchannel with gradually contracted cross-section and high aspect ratio (the ratio of the height to the average width of channel) is utilized to enhance the hydrodynamic force and change the force direction, eventually leading to the efficient enrichment of nano-/submicroparticles (500 and 860 nm) in a short channel length (2 cm). The influence of the flow rate, the particle size, the solid concentration, and the channel geometry on the enrichment of the nano-/submicroparticles are investigated. With simple structure, small footprint, easy operation, and good performance, the present device would be a promising platform for various lab-chip microvesicle-related biomedical research and disease diagnosis.

Identification of Two Novel Frameshift Mutations in Exostosin 1 in Two Families with Multiple Osteochondromas

Multiple osteochondromas (MO) is an autosomal dominant hereditary disorder, which typically manifests as skeletal dysplasia, mainly involving long bones and knees, ankles, elbows, wrists, shoulders, and pelvis. Previous studies have demonstrated that mutations in exostosin glycosyl transferase-1 (EXT1) and exostosin glycosyl transferase-2 (EXT2) were the main cause of MO. In this study, we enrolled 2 families with MO. Sanger sequencing revealed 2 novel frameshift mutations - c.1432_1433insCCCCCCT; p.Lys479Profs*44 and c.1431_1431delC; p.S478PfsX10 - in the EXT1 gene detected in 2 families, respectively. Both novel mutations, located in the conserved domain of EXT1 and predicted to be disease causing by informatics programs, were absent in our 200 control cohorts and other public databases. Our study expanded the spectrum of EXT1 mutations and contributed to genetic diagnosis and counseling of patients with MO.

Case Report: Chorea-Acanthocytosis Presents as Epilepsy in a Consanguineous Family With a Nonsense Mutation of in VPS13A

Chorea-Acanthocytosis (ChAc), a rare autosomal recessive inherited neurological disorder, originated from variants in Vacuolar Protein Sorting 13 homolog A (VPS13A) gene. The main symptoms of ChAc contain hyperkinetic movements, seizures, cognitive impairment, neuropsychiatric symptoms, elevated serum biochemical indicators, and acanthocytes detection in peripheral blood smear. Recently, researchers found that epilepsy may be a presenting and prominent symptom of ChAc. Here, we enrolled a consanguineous family with epilepsy and non-coordinated movement. Whole exome sequencing was employed to explore the genetic lesion of the family. After data filtering, co-separation analysis was performed by Sanger sequencing and bioinformatics analysis, the homozygous nonsense variant (NM_033305.2: c.8282C>G, p.S2761X) of VPS13A were identified which could be genetic factor of the patient. No other meaningful mutations were detected. This mutation (p.S2761X) led to a truncated protein in exon 60 of the VPS13A gene, was simultaneously absent in our 200 local control participants. The homozygous mutation (NM_033305.2: c.8282C>G, p.S2761X) of VPS13A may be the first time be identified in ChAc patient with epilepsy. Our study assisted to the diagnosis of ChAc in this patient and contributed to the genetic diagnosis and counseling of families with ChAc presented as epilepsy. Moreover, we further indicated that epilepsy was a crucial phenotype in ChAc patients caused by VPS13A mutations.

A Novel Homozygous Variant of TMEM231 in a Case With Hypoplasia of the Cerebellar Vermis and Polydactyly

Background: Transmembrane protein 231 (TMEM231) is a component of the B9 complex that participates in the formation of the diffusion barrier between the cilia and plasma membrane. Mutations in TMEM231 gene may contribute to the Joubert syndrome (JBTS) or Meckel-Gruber syndrome (MKS). However, reports on JBTS or MKS caused by TMEM231 mutations are comparatively rare. Method: We describe a Chinese fetus with unexplained hypoplasia of the cerebellar vermis and polydactyly, detected by ultrasound imaging. The fetus was primarily diagnosed with JBTS/MKS. The parents of this fetus were non-consanguineous and healthy. Whole-exome sequencing (WES) and bioinformatics strategies were employed to explore the genetic lesion of this family. Results: An unknown missense variant (c.19C>T;p.R7W) of TMEM231 gene was detected. The variant was predicted as pathogenic and was absent in our 200 healthy controls. Conclusion: WES was employed to explore the genetic lesion of a fetus with unexplained hypoplasia of the cerebellar vermis and polydactyly. A novel variant in TMEM231 gene was identified. Our study not only provided data for genetic counseling and prenatal diagnosis to this family but also broadened the spectrum of TMEM231 mutations.

Case Report: Exome Sequencing Identified a Novel Frameshift Mutation of α-Actin 1 in a Chinese Family With Macrothrombocytopenia and Mild Bleeding

Inherited macrothrombocytopenia (IMTP) is a rare disorder characterized by a reduced platelet count and abnormally large platelets. The main clinical symptom of IMTP is mild bleeding in some patients. At present, more than 30 genes have been identified in patients with syndromic and non-syndromic IMTP. In this study, a 3-year-old boy and his mother who presented with mild epistaxis and/or gingival bleeding were diagnosed as having IMTP. Wen then selected whole sequencing to explore the genetic lesion of the patients. After data filtering and mutation validation, a novel frameshift mutation (NM_001130004: c.398_399insTGCG, p.F134AfsX60) of α-actin 1 (ACTN1) was identified in the proband and his mother but absent in other unaffected individuals. Previous studies have proven that mutations in ACTN1 may lead to IMTP with mild to absent bleeding phenotype. The novel mutation, resulting in a truncated protein in exon 4 of the ACTN1 gene, was absent in the public database, such as 1000G and genomAD. Further Western blot revealed that the expression of α-actin 1 in the proband was decreased overtly, which indicated that the novel frameshift mutation may induce non-sense-mediated mRNA decay. In summary, this study not only broadened the variants spectrum of ACTN1 gene, which may contribute to the genetic counseling of IMTP, but also confirmed the diagnosis of IMTP, which may help the management and prognosis for the family members.

A Novel Nonsense MMP21 Variant Causes Dextrocardia and Congenital Heart Disease in a Han Chinese Patient

The position and morphology of human internal organs are asymmetrically distributed along the left-right axis. Aberrant left-right patterning in the developing embryo can lead to a series of congenital laterality defects, such as dextrocardia and heterotaxy syndrome. Laterality defects are a genetic condition; however, pathogenic genetic lesions are found in only one-fifth of patients. In this study, whole-exome sequencing was conducted for 78 patients with laterality defects. We identified a novel stopgain variant in MMP21 (c.G496T; p.G166^*) in a Chinese patient with mirror-image dextrocardia. This variant caused a truncated MMP21 mRNA containing only the signal peptide and propeptide, while the coding sequence of matrix metalloproteinase-21 was almost entirely absent. To the best of our knowledge, this novel variant is the first homozygous stopgain variant identified in dextrocardia patients, and the first MMP21 variant found in East Asia. Our findings expand the spectrum of MMP21 variants and provide support for the critical role of MMP21 during left-right patterning in the Han Chinese population.

A novel heterozygous variant of the COL4A4 gene in a Chinese family with hematuria and proteinuria leads to focal segmental glomerulosclerosis and chronic kidney disease

Background

Focal segmental glomerulosclerosis (FSGS), as the frequent primary glomerular diseases in adults, accounts for symptomless proteinuria or nephrotic syndrome with or without renal insufficiency. As the crucial lesion of chronic kidney disease (CKD), accumulating evidence from recent studies show that mutations in Collagen‐related genes may be responsible for FSGS. The aim of this study was to identify the genetic lesion of a Chinese family with FSGS and CKD.

Methods

In this study, we recruited a Han‐Chinese family with unexplained high serum creatinine, hematuria, and proteinuria. Further renal biopsy and renal pathology indicated the diagnosis of FSGS in the proband. Whole‐exome sequencing and Sanger sequencing were employed to explore the pathogenic mutation of this family.

Results

A novel heterozygous mutation (NM_000092 c.2030G>A, p.G677D) of the collagen type IV alpha‐4 gene (COL4A4) was detected. Co‐segregation analysis revealed that the novel mutation was carried by all the five affected individuals and absent in other healthy members as well as in our 200 local control cohorts. Bioinformatics predication indicated that this novel mutation was pathogenic and may disrupt the structure and function of type IV collagen. Simultaneously, this variant is located in an evolutionarily conserved site of COL4A4 protein.

Conclusion

Here, we identified a novel mutation of COL4A4 in a family with FSGS and CKD. Our study expanded the variants spectrum of the COL4A4 gene and contributed to the genetic counseling and prenatal genetic diagnosis of the family. In addition, we also recommended the new classification of collagen IV nephropathies, which may be a benefit to the diagnosis, target drug treatment, and management of patients with COL4A3/COL4A4 mutations.

Identification of a Novel Arginine Vasopressin Receptor 2 Mutation (p.V183M) in a Chinese Family with Nephrogenic Diabetes Insipidus

Loss of function of arginine vasopressin receptor 2 (AVPR2) may affect the recognition and binding of arginine vasopressin (AVP) which, in turn, may prevent the activation of Gs/adenylate cyclase and reduce the reabsorption of water by renal tubules and combined tubes. Finally, the organism may suffer from nephrogenic diabetes insipidus (NDI), a kind of kidney disorder featured by polyuria and polydipsia, due to a break of water homeostasis. In this study, we enrolled a Chinese family with polyuria and polydipsia. The proband presented abnormal fluid intake and excessive urine output. A water deprivation and AVP stimulation test further indicated that this patient had NDI. By sequencing known causative genes for diabetes insipidus, we identified a novel mutation in AVPR2 (c.547G>A; p.V183M) in the family. This mutation, located in a conserved site of AVPR2 and predicted to be disease-causing by informatics programs, was absent in our 200 controls and other public databases. Our study not only further confirms the clinical diagnosis, but also expands the spectrum of AVPR2 mutations and contributes to genetic diagnosis and counseling of patients with NDI.

A Novel Nonsense Mutation of ABCA8 in a Han-Chinese Family With ASCVD Leads to the Reduction of HDL-c Levels

Arteriosclerotic cardiovascular disease (ASCVD) is one of the major causes of death worldwide and most commonly develops as a result of atherosclerosis (AS). As we all know, dyslipidemia is a leading pathogenic risk factor for ASCVD, which leads to cardiac ischemic injury and myocardial infarction. Dyslipidemias include hypercholesterolemia, hypertriglyceridemia, increased low-density lipoprotein cholesterol (LDL-c) and decreased high density lipoproteins cholesterol (HDL-c). Mutations of dyslipidemia related genes have been proved to be the crucial contributor to the development of AS and ASCVD. In this study, a Han-Chinese family with ASCVD was enrolled and the lipid testing discovered an obvious reduced levels of HDL-c in the affected members. We then performed whole exome sequencing to detect the candidate genes of the family. After data filtering, a novel heterozygous nonsense mutation (NM_007168: c.3460C>T; p.R1154X) of ABCA8 was detected and validated to be co-separated in the family members by Sanger sequencing. Previous studies have proved that deleterious heterozygous ABCA8 variants may disrupt cholesterol efflux and reduce HDL-c levels in humans and mice. This study may be the second report related to ABCA8 mutations in patients with reduced levels of HDL-c. Our study not only contributed to the genetic counseling and prenatal genetic diagnosis of patients with ASCVD caused by reduced HDL-c levels, but also provided a new sight among ABCA8, cholesterol efflux and HDL-c levels.

Novel Compound Heterozygous DST Variants Causing Hereditary Sensory and Autonomic Neuropathies VI in Twins of a Chinese Family

Background: Hereditary sensory and autonomic neuropathies (HSANs) are a rare and severe group of sensory axonal neuropathies. HSANs have been classified into eight groups based on mode of inheritance, clinical features, and the involved genes. HSAN-VI, perhaps the most notable type, is an autosomal recessive disease, which manifests as the severely impaired pain sensitivity, autonomic disturbances, distal myopathy, spontaneous or surgical amputations, and sometimes early death. Mutations in DST have been identified as the cause of HSAN-VI. DST encodes dystonin, a member of the plakin protein family that is involved in cytoskeletal filament networks. Dystonin has seven major isoforms in nerve, muscle, and epithelium.

Material and Methods: The present study investigated a Chinese family with HSAN and explored potential pathogenic variants using whole-exome sequencing (WES). Variants were screened and filtered through bioinformatics analysis and prediction of variant pathogenicity. Co-segregation analysis was subsequently conducted.

Results: We identified compound heterozygous variants of DST (c.3304G>A, p.V1102I and c.13796G>A, p.R4599H) in two patients.

Conclusion: We reported on a Chinese family with HSAN-VI family and detected the disease-causing variants. Our description expands the spectrum of known DST variants and contributes to the clinical diagnosis of HSAN-VI.

A Novel Heterozygous Variant in F2 Gene in a Chinese Patient With Coronary Thrombosis and Acute Myocardial Infarction Leads to Antithrombin Resistance

Thrombophilia refers to a group of conditions where the blood clots more easily than normal. These blood clots can cause problems such as deep vein thrombosis or pulmonary embolism. Most kinds of mutated coagulation factors II (F2) exhibit lower procoagulant activity, but in some cases, a higher coagulation rate has been observed. The underlying mechanism is that those variations can prevent F2s from being inhibited by antithrombin, leading to a contiguous activation of procoagulation, and causing recurrent thromboembolism. In this study, a patient was admitted to our hospital due to repeated chest pain for 2 days and aggravated for 4 h. A medical history investigation showed that he had three deep venous thromboses in the lower limbs and one portal vein thrombosis events during the past 10 years. The electrocardiogram showed Q wave elevation and slight ST segment elevation in lead V2, and coronary angiogram showed a total occlusion of the left anterior descending artery. Laboratory testing found that troponin I was obviously elevated. Family history also indicated that both his father (II-3) and grandfather (I-1) died from pulmonary thromboembolism. Whole-exome sequencing was performed to detect the genetic lesion of the patient, and a novel mutation (c.1621 C>T/p.R541W) of F2 was identified in the patient. This novel mutation resulted in a substitution of arginine by tryptophan, leading to antithrombin resistance (ATR). Our study is consistent with previously published papers. In conclusion, this study not only identifies a novel mutation of F2 and will contribute to the genetic diagnosis and counseling of families with thrombosis but also suggests that the site p.R541 of F2 may play a crucial role in thrombosis.

A de novo mutation of SMYD1 (p.F272L) is responsible for hypertrophic cardiomyopathy in a Chinese patient

Background Hypertrophic cardiomyopathy (HCM) is a serious disorder and one of the leading causes of mortality worldwide. HCM is characterized as left ventricular hypertrophy in the absence of any other loading conditions. In previous studies, mutations in at least 50 genes have been identified in HCM patients. Methods In this research, the genetic lesion of an HCM patient was identified by whole exome sequencing. Real-time polymerase chain reaction (PCR), immunofluorescence and Western blot were used to analyze the effects of the identified mutation. Results According to whole exome sequencing, we identified a de novo mutation (c.814T>C/p.F272L) of SET and MYND domain containing histone methyltransferase 1 (SMYD1) in a Chinese patient with HCM exhibiting syncope. We then generated HIS-SMYD1-pcDNA3.1+ (WT and c.814T>C/p.F272L) plasmids for transfection into AC16 cells to functionalize the mutation. The immunofluorescence experiments indicated that this mutation may block the SMYD1 protein from entering the nucleus. Both Western blot and real-time PCR revealed that, compared with cells transfected with WT plasmids, the expression of HCM-associated genes such as β-myosin heavy chains, SMYD1 chaperones (HSP90) and downstream targets including TGF-β were all disrupted in cells transfected with the mutant plasmid. Previous studies have demonstrated that SMYD1 plays a crucial role in sarcomere organization and heart development. Conclusions This novel mutation (c.814T>C/p.F272L) may be the first identified disease-causing mutation of SMYD1 in HCM patients worldwide. Our research expands the spectrum of HCM-causing genes and contributes to genetic counseling for HCM patients.

Identification of a novel mutation of NOG in family with proximal symphalangism and early genetic counseling

BACKGROUND

Proximal symphalangism is a rare disease with multiple phenotypes including reduced proximal interphalangeal joint space, symphalangism of the 4th and/or 5th finger, as well as hearing loss. At present, at least two types of proximal symphalangism have been identified in the clinic. One is proximal symphalangism-1A (SYM1A), which is caused by genetic variants in Noggin (NOG), another is proximal symphalangism-1B (SYM1B), which is resulted from Growth Differentiation Factor 5 (GDF5) mutations.

CASE PRESENTATION

Here, we reported a Chinese family with symphalangism of the 4th and/or 5th finger and moderate deafness. The proband was a 13-year-old girl with normal intelligence but symphalangism of the 4th finger in the left hand and moderate deafness. Hearing testing and inner ear CT scan suggested that the proband suffered from structural deafness. Family history investigation found that her father (II-3) and grandmother (I-2) also suffered from hearing loss and symphalangism. Target sequencing identified a novel heterozygous NOG mutation, c.690C > G/p.C230W, which was the genetic lesion of the affected family. Bioinformatics analysis and public databases filtering further confirmed the pathogenicity of the novel mutation. Furthermore, we assisted the family to deliver a baby girl who did not carry the mutation by genetic counseling and prenatal diagnosis using amniotic fluid DNA sequencing.

CONCLUSION

In this study, we identified a novel NOG mutation (c.690C > G/p.C230W) by target sequencing and helped the family to deliver a baby who did not carry the mutation. Our study expanded the spectrum of NOG mutations and contributed to genetic diagnosis and counseling of families with SYM1A.

Increased Reticulon 3 (RTN3) Leads to Obesity and Hypertriglyceridemia by Interacting With Heat Shock Protein Family A (Hsp70) Member 5 (HSPA5)

BACKGROUND

Reticulon 3 (RTN3) is an endoplasmic reticulum protein that has previously been shown to play a role in neurodegenerative diseases, but little is known about its role in lipid metabolism.

METHODS

Obese patients (n=149), hypertriglyceridemic patients (n=343), and healthy control subjects (n=84) were enrolled to assess their levels of RTN3. To explore the pathophysiological roles of RTN3 in the control of lipid metabolism, we used transgenic mice overexpressing the wild-type human RTN3 gene, the RTN3-null transgenic mouse model, and multiple Caenorhabditis legans strains for molecular characterization. The underlying mechanisms were studied with 3T3L1 cell cultures in vitro.

RESULTS

We report that overexpressed RTN3 in mice induces obesity and higher accumulation of triglycerides. Increased RTN3 expression is also found in patients with obesity and hypertriglyceridemia. We reveal that RTN3 plays critical roles in regulating the biosynthesis and storage of triglycerides and in controlling lipid droplet expansion. Mechanistically, RTN3 regulates these events through its interactions with heat shock protein family A (Hsp70) member 5, and this enhanced interaction increases sterol regulatory element-binding protein 1c and AMP-activated kinase activity.

CONCLUSIONS

This study provides evidence for a role of RTN3 in inducing obesity and triglyceride accumulation and suggests that inhibiting the expression of RTN3 in fat tissue may be a novel therapeutic approach to treat obesity and hypertriglyceridemia.

Compound heterozygous GNPTAB mutations cause mucolipidosis II or III alpha/beta in two Chinese families

OBJECTIVE

Mucolipidosis II and III alpha/beta (ML II & ML III alpha/beta) are rare autosomal recessive lysosomal storage disorders. ML II is clinically evident from birth with a progressive course and fatal outcome in childhood. The typical phenotypes of ML II include limited statural growth, craniofacial abnormality, skeletal malformation, intelligence developmental deficiency and visceral organ abnormality. ML III is milder than ML II. Mutations in GNPTAB cause the ML II/III.

METHODS

Two families with ML II/III (initially undiagnosed) were recruited. We applied whole-exome sequencing (WES) and filtered mutations by genes causing lysosomal storage diseases with skeletal involvement. Mutational analysis and co-segregation confirmation were then performed.

RESULTS

We presented two families with ML II or ML III alpha/beta. By WES, the compound heterozygosity of GNPTAB (c.2404C>T, p.Q802* and c.2590dup, p.E864Gfs*4) is identified in a family with ML II, and c.1364C>T, p.A455V and c.2715+1G>A are detected in a family with ML III alpha/beta.

CONCLUSION

We detected the causative mutations in two ML II/III families by WES and confirmed their diagnosis of the diseases. The present identification of mutations expands the spectrum of known GNPTAB mutations and it may contribute to novel approaches to genetic diagnosis and counseling for patients with ML II/III.

[Study on the relationship between preoperative evaluation, operation and prognosis of microvascular decompression for the treatment of hemifacial spasm]

Objective: To investigate the relationship between preoperative evaluation, surgery and prognosis of microvascular decompression (MVD) for the treatment of hemifacial spasm (HFS). Methods: The clinical data of 128 HFS patients treated with MVD in the department of neurosurgery of Taizhou Hospital of Zhejiang Province were retrospectively analyzed. According to the SMC grading system, the patients were divided into general spasm group and severe spasm group, and the clinical characteristics, offending vessel, prognosis and surgical complications of the two groups were compared. Results: In the general spasm group,the age at MVD was (48.6±10.6) years, the disease duration was (4.2±3.3) years;while in the severe spasm group,the age at MVD was (51.8±9.9) years, the disease duration was (8.1±4.5) years;the differences of age and disease duration between the two groups were statistically significant (P<0.05).In the general spasm group, there were 41 cases in which the offending vessel were AICA, 21 cases were PICA, 1 case was VA, 63 cases were single offending vessel, and 7 cases were multiple offending vessels. In the severe spasm group, there were 29 cases in which the offending vessel were AICA, 13 cases were PICA, 2 cases were VA, the total of 44 cases were single offending vessel and 14 cases were multiple offending vessels.There was a significant difference in the proportion of multiple offending vessels in the two groups, and the difference was statistically significant (P<0.05).Patients in the two groups were followed up for 12 to 32 months after surgery, and the difference in effective rate and recurrence rate was not statistically significant (P>0.05).Some kinds of postoperative complications were different between the two groups, the incidence of postoperative delayed facial paralysis was statistically significant (P<0.05), and the other complications were not statistically significant (P>0.05). Conclusion: Compared with the general spasm group, the patients in the severe spasm group were older, with longer disease duration, higher probability of multiple offending vessels and higher incidence of postoperative delayed facial paralysis. Therefore, preoperative SMC grading is helpful for the evaluation and prediction of intraoperative and postoperative conditions, which is worthy of wide clinical application.

Whole exome sequencing identified a novel mutation (p.Ala1884Pro) of β-spectrin in a Chinese family with hereditary spherocytosis

BACKGROUND

Hereditary spherocytosis (HS) is an inherited disorder of erythrocyte. The typical feature of HS is the presence of spherical-shaped erythrocytes on the peripheral blood smear. According to previous studies, more than five candidate genes, such as ANK1, SPTB, SPTA1, SLC4A1 and EPB42 have been identified in HS patients.

METHODS

In the present study, a Chinese HS family was investigated. The proband suffered from pathologic jaundice and splenomegaly. A blood test and peripheral blood smear experiment further confirmed the diagnosis of HS. We selected the proband to perform the whole exome sequencing.

RESULTS

After data filtering and co-segregation analysis, we identified 12 mutations in affected members that were absent in healthy members. In consideration of the inheritance pattern, Online Mendelian Inheritance in Man clinical phenotypes, Toppgene function and American College of Medical Genetics classification, we considered the novel mutation (c.5650G > C/p.Ala1884Pro) of β-spectrin (SPTB) to be the genetic lesion in this family. The novel mutation, resulting in a substitution of alanine by proline, may lead to transformation of the SPTB protein structure, which affects the binding between SPTB and ankyrin.

CONCLUSIONS

The present study confirmed the hereditary red blood cell membrane disorders at a molecular level and expanded the spectrum of SPTB mutations. This may contribute to the clinical management and genetic counseling with respect to HS.

Whole-Exome Sequencing Identifies a Novel Mutation (p.L320R) of Alpha-Actinin 2 in a Chinese Family with Dilated Cardiomyopathy and Ventricular Tachycardia

Dilated cardiomyopathy (DCM) is a severe cardiovascular disease which can lead to heart failure and sudden cardiac death (SCD). The typical feature of DCM is left ventricular enlargement or dilatation. In some conditions, DCM and arrhythmia can occur concurrently, apparently promoting the prevalence of SCD. According to previous studies, mutations in more than 100 genes have been detected in DCM and/or arrhythmia patients. Here, we report a Chinese family with typical DCM, ventricular tachycardia, syncope, and SCD. Using whole-exome sequencing, a novel, likely pathogenic mutation (c.959T>G/p.L320R) of actinin alpha 2 (ACTN2) was identified in all affected family members. This novel mutation was also predicted to be disease-causing by MutationTaster, SIFT, and Polyphen-2. Our study not only expands the spectrum of ACTN2 mutations and contributes to the genetic diagnosis and counseling of the family, but also provides a new case with overlap phenotype that may be caused by the ACTN2 variant.