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A rare and challenging case of a preterm neonate with clinical and radiological signs of respiratory distress syndrome (RDS) since the first hour of life but was refractory to its standard treatment regimes like surfactant therapy and ventilation. Postmortem lung biopsy led us to the diagnosis of congenital pulmonary alveolar proteinosis (PAP). It occurs due to the aggregation of abnormal surfactant proteins and lipids in the alveoli, which hampers gas diffusion across the alveoli. It presents as respiratory distress at birth, and its diagnosis is often missed due to its resemblance with RDS. Although the exact etiology remains elusive, mutations in genes encoding surfactant and granulocyte-macrophage colony-stimulating factor (GM-CSF) pathway components have been implicated in the pathogenesis of PAP. Treatment options are limited and only supportive. Among all these, whole-lung lavage is the most widely used management modality but with limited success in neonates.
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BACKGROUND: Exercise-induced pulmonary haemorrhage (EIPH) in athletic horses is characterized by the presence of blood from the lungs in the tracheobronchial tree after intense exercise. Despite the high prevalence of EIPH in horses, the primary aetiology remains unknown. Variants in the genes encoding CD39 and CD39L1 (ENTPD1 and ENTPD2, respectively) were previously reported as potential genetic causes involved in EIPH pathogenesis. However, the role of these variants in haemostatic functions is unknown. RESULTS: To investigate the association between EIPH and missense variants in the ENTPD1 (rs1152296272, rs68621348, and rs68621347) and ENTPD2 genes (rs782872967), 76 Thoroughbred horses diagnosed with EIPH and 56 without clinical signs of EIPH (control group) by trachea-bronchial endoscopy were genotyped. The rs1152296272 and rs68621347 variants were linked, which explained why the same results were found in all horses. Approximately 96% and 95% of the EIPH and control horses, respectively, carried at least one nonreference allele for these variants. In contrast, 100% of the control horses and 96% of the EIPH horses were homozygous for the reference allele for the rs68621348 variant. In the EIPH group, 1.5% of the horses were homozygotes and 24% were heterozygous for the nonreference allele of the rs782872967 variant. In the control group, the nonreference allele of this variant was observed only in heterozygotes (16%). There were no significant differences between groups for any of the variants. CONCLUSIONS: The variants previously described in the genes encoding the CD39 and CD39L1 enzymes were highly present in the studied population. However, no association was found between the occurrence of EIPH and the presence of these variants in Thoroughbred horses in this study.
Subject(s)
Hemorrhage , Horse Diseases , Lung Diseases , Physical Conditioning, Animal , Animals , Horses , Horse Diseases/genetics , Hemorrhage/veterinary , Hemorrhage/genetics , Lung Diseases/veterinary , Lung Diseases/genetics , Male , Apyrase/genetics , Female , Genetic Predisposition to Disease , Genotype , Mutation, MissenseABSTRACT
Alkaptonuria is a rare autosomal recessive congenital disorder of metabolism that affects 1 in 250,000 live births. It manifests as ochronosis and degenerative arthritis due to the accumulation of homogentistic acid in cartilage and heart valves along with precipitation of renal, salivary, pancreatic and gall bladder calculi. It is noted to cause cardiac valve stenosis and regurgitation secondary to calcification leading to cardiac failure in 10% of patients. Through this report, we present a successful perioperative anaesthetic management of a 74-year-old man with cardiac ochronosis, who underwent an aortic valve replacement with coronary artery bypass graft surgery at our centre.
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Osteochondrosis (OC) is a developmental orthopaedic disease of significant concern in numerous sport horse breeds, with significant international relevance. Using digital radiographs, we assessed the occurrence of hock (tarsocrural joint) OC in 3 048 Pura Raza Española (PRE) horses which took part in a morpho-functional test, in three specific locations in the tarsus limbs: the Distal Intermediate Ridge of the Tibia (DIRT), the lateral trochlear ridges of the talus (LTT), and the medial trochlear ridges of the talus (MTT). An incidence rate of 13.3% was found for hock OC in the analysed sample, with the highest incidence rate observed in DIRT (10.0%) and the lowest in MTT (0.2%). Estimates of genetic predisposition to hock OC were carried out using three genetic approaches: 1a) a binomial threshold model based on the presence or absence of OC, 1b) a multinomial threshold model, on a scale from 0 (absence) to 3 (maximum), and 2) a linear model. The effects considered in the models included sex, genetic origin and stud class. All the analyses were based on the Bayesian inference methodology, using the THRGIBBS3F90 software. The binomial threshold model yielded the most suitable results, with an estimated heritability for Overall hock OC of 0.71 ± 0.055 on the underlying scale (0.53 on the observed scale), ranging in different locations from 0.48 ± 0.087 (LTT) to 0.66 ± 0.063 (DIRT) on the underlying scale (0.10 and 0.38 on the observed scale, respectively). The highest significative genetic correlation was observed between Overall and DIRT (0.97) for approach 1a, and the lowest significant genetic correlation was between Overall and LTT (0.49), for approach 2. This study contributes valuable insights into the genetic predisposition towards, as well as for the potential for selective breeding against, hock OC in PRE horses, and provides a basis for future research and breeding programmes aimed at minimising the occurrence of hock OC and promoting the overall health of this breed.
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Background: Preimplantation genetic testing (PGT) can reduce the risk of familial genetic diseases, chromosome abnormalities, and recurrent abortions. It is unclear whether genetic counselees with PGT indications understand and accept the implications of PGT. A well-developed and validated tool is needed to evaluate the knowledge, attitude, and practice (KAP) levels of genetic counselees with PGT indications. The purpose of this study was to develop and validate a PGT KAP questionnaire (PGT-KAP-Q) for genetic counselees with PGT indications. Methods: First, we established an item pool based on a literature review and qualitative interviews. Second, we developed the PGT-KAP-Q using the Delphi method. Third, we evaluated the quality of the questionnaire using item analysis and psychometric evaluation. The item analysis included extreme value comparison, application of the correlation and Cronbach's alpha (α) coefficient methods, and factor analysis. We also evaluated the content and structural validity of the questionnaire, as well as the internal consistency, test-retest reliability, and split-half reliability. Findings: After the literature review and interviews, and based on three rounds of expert consultations, we formed a 43-item questionnaire. In the validity analysis, the item's content validity index (I-CVI) and the average scale level CVI (S-CVI/Ave) values (>0.78 and >0.95, respectively) confirmed the questionnaire's content validity. Exploratory factor analysis showed that all 43 items had strong factor loadings (>0.4), and the three factors of the PGT-KAP-Q explained 51.97 % of the total variance. The Cronbach's α coefficient for the questionnaire was 0.95 (p < 0.05), the split-half reliability was 0.76 (p < 0.05) and the test-retest reliability coefficient was 0.78 (p < 0.05). Interpretation: The 43-item PGT-KAP-Q for genetic counselees with PGT indications is reliable and valid. It contains a moderate number of items, is easy for patients to understand and accept, and can be used for clinical research and applications.
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The global prevalence rate for congenital hydrocephalus (CH) is approximately one out of every five hundred births with multifaceted predisposing factors at play. Genetic influences stand as a major contributor to CH pathogenesis, and epidemiological evidence suggests their involvement in up to 40% of all cases observed globally. Knowledge about an individual's genetic susceptibility can significantly improve prognostic precision while aiding clinical decision-making processes. However, the precise genetic etiology has only been pinpointed in fewer than 5% of human instances. More occurrences of CH cases are required for comprehensive gene sequencing aimed at uncovering additional potential genetic loci. A deeper comprehension of its underlying genetics may offer invaluable insights into the molecular and cellular basis of this brain disorder. This review provides a summary of pertinent genes identified through gene sequencing technologies in humans, in addition to the 4 genes currently associated with CH (two X-linked genes L1CAM and AP1S2, two autosomal recessive MPDZ and CCDC88C). Others predominantly participate in aqueduct abnormalities, ciliary movement, and nervous system development. The prospective CH-related genes revealed through animal model gene-editing techniques are further outlined, focusing mainly on 4 pathways, namely cilia synthesis and movement, ion channels and transportation, Reissner's fiber (RF) synthesis, cell apoptosis, and neurogenesis. Notably, the proper functioning of motile cilia provides significant impulsion for cerebrospinal fluid (CSF) circulation within the brain ventricles while mutations in cilia-related genes constitute a primary cause underlying this condition. So far, only a limited number of CH-associated genes have been identified in humans. The integration of genotype and phenotype for disease diagnosis represents a new trend in the medical field. Animal models provide insights into the pathogenesis of CH and contribute to our understanding of its association with related complications, such as renal cysts, scoliosis, and cardiomyopathy, as these genes may also play a role in the development of these diseases. Genes discovered in animals present potential targets for new treatments but require further validation through future human studies.
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Hydrocephalus , Humans , Hydrocephalus/genetics , Hydrocephalus/etiology , Animals , Genetic Predisposition to DiseaseABSTRACT
Abstract Background Neurofibromatosis type 1 (NF1) is a rare genetic disorder with a wide range of clinical manifestations, notably neurocutaneous features, that can lead to emotional and physical consequences. Objectives This study assessed the influence of sociodemographic factors and clinical features of the disease on the quality of life of Brazilian individuals with NF1. Methods This is a descriptive cross-sectional study. Data were collected from 101 individuals with NF1 using the Brazilian version of the Impact of NF1 on Quality of Life Questionnaire (INF1-QoL), a form with information on sociodemographic characteristics, and an NF1 visibility self-evaluation scale. The relationship between variables was evaluated through statistical testing, and the significance level was defined as 0.05. Results The study included 101 adults with NF1 aged 18 to 59 years, with a mean age of 35.54 years (±9.63) and a female predominance (n = 84, 83.17%). The mean total INF1-QoL score was 10.62 (±5.63), with a median of 10, minimum value of 0, and maximum of 31 points. Two characteristics of the participants were significantly associated with the quality of life: educational level (p = 0.003) and familial history of NF1 (p = 0.019). There was a statistically significant correlation between the INF1-QoL score and the degree of disease visibility (rho = 0.218; p = 0.028). Study limitations Cross-sectional study, conducted with a convenience sample and using self-reported measures. Conclusions The findings support the significant impact of NF1 on quality of life. The authors recommend multidisciplinary follow-up for patients, with adherence to anticipatory clinical care measures, adequate pain control, psychological assistance, and genetic counseling.
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Background and Aims: Real-world analyses on burden of illness in patients with alpha-1 antitrypsin deficiency (AATD) are limited. We investigated the real-world burden of liver-related clinical events among adult and pediatric patients with AATD in the USA. Methods: This was a retrospective, observational analysis of administrative claims data from the IQVIA PharMetrics® Plus and Ambulatory Electronic Medical Records databases from 2011 to 2022. Patients had a diagnosis of liver and/or lung disease with ≥180 days of continuous enrollment in the IQVIA PharMetrics Plus database before and ≥90 days after their first diagnosis. Follow-up time was assigned to the AATD with liver disease health state or AATD with both liver and lung disease health state (for patients aged ≥18 years only). Baseline demographic characteristics and liver-related clinical events of interest were reported. Results: Of 5136 eligible patients, 771 adult and 123 pediatric patients contributed time to the AATD with liver disease health state; 541 adults contributed time to the AATD with both liver and lung disease health state. Among adults, patients with both liver and lung disease had higher rates of liver-related clinical events than patients with liver disease alone. Ascites was the most frequently observed clinical event among adults in both health states, and the median time to the composite of any liver-related clinical event was 26.5 days among all adults combined. Across all pediatric age groups, ascites, gastrointestinal bleed and hepatic encephalopathy were more common than spontaneous bacterial peritonitis and hepatocellular carcinoma, but median time to liver-related clinical event varied by age group at index date and type of event. No liver transplantations occurred in patients aged 6-17 years. Conclusion: Diagnosed AATD with liver disease carries a substantial burden on adult and pediatric patients; new treatment options are warranted to avoid disease progression to decompensating events.
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Blood Platelets , Hemorrhage , Phosphatidylserines , Humans , Blood Platelets/metabolism , Hemorrhage/blood , Male , Female , Pedigree , Syndrome , AdultABSTRACT
The Na,K-ATPase is an α-ß heterodimer. It is well known that the Na,K-ATPase ß subunit is required for the biosynthesis and trafficking of the α subunit to the plasma membrane. During investigation of properties of human ATP1A3 mutations in 293 cells, we observed a reciprocal loss of endogenous ATP1A1 when expressing ATP1A3. Scattered reports going back as far as 1991 have shown that experimental expression of one subunit can result in reduction in another, suggesting that the total amount is strictly limited. It seems logical that either α or ß subunit should be rate-limiting for assembly and functional expression. Here, we present evidence that neither α nor ß may be limiting and that there is another level of control that limits the amount of Na,K-ATPase to physiological levels. We propose that α subunits compete for something specific, like a private chaperone, required to finalize their biosynthesis or to prevent their degradation in the endoplasmic reticulum.
Subject(s)
Protein Subunits , Sodium-Potassium-Exchanging ATPase , Sodium-Potassium-Exchanging ATPase/metabolism , Sodium-Potassium-Exchanging ATPase/genetics , Humans , Protein Subunits/metabolism , Protein Subunits/genetics , HEK293 Cells , Mutation , Animals , Endoplasmic Reticulum/metabolismABSTRACT
BACKGROUND: The 22q11.2 Deletion Syndrome (22q11.2 DS) presents unique healthcare challenges for affected individuals, families, and healthcare systems. Despite its rarity, 22q11.2 DS is the most common microdeletion syndrome in humans, emphasizing the need to understand and address the distinctive healthcare requirements of those affected. This paper examines the multifaceted issue of health service access and caregivers' quality of life in the context of 22q11.2 DS in Brazil, a condition with diverse signs and symptoms requiring multidisciplinary care. This study employs a comprehensive approach to evaluate health service accessibility and the quality of life of caregivers of individuals with 22q11.2 DS. It utilizes a structured Survey and the WHOQOL-bref questionnaire for data collection. RESULTS: Individuals with 22q11.2 DS continue to receive incomplete clinical management after obtaining the diagnosis, even in the face of socioeconomic status that enabled an average age of diagnosis that precedes that found in sample groups that are more representative of the Brazilian population (mean of 3.2 years versus 10 years, respectively). In turn, caring for individuals with 22q11.2 DS who face difficulty accessing health services impacts the quality of life associated with the caregivers' environment of residence. CONCLUSIONS: Results obtained help bridge the research gap in understanding how caring for individuals with multisystem clinical conditions such as 22q11.2 DS and difficulties in accessing health are intertwined with aspects of quality of life in Brazil. This research paves the way for more inclusive healthcare policies and interventions to enhance the quality of life for families affected by this syndrome.
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DiGeorge Syndrome , Health Services Accessibility , Quality of Life , Humans , Brazil , Male , Female , Child , Adult , Adolescent , Caregivers/psychology , Child, Preschool , Surveys and Questionnaires , Young AdultABSTRACT
The International Committee on Classification of Corneal Dystrophies (IC3D) was founded in 2005 to address difficulties arising from the outdated nomenclature for corneal dystrophies (CD) and to correct misconceptions in the literature. For each of the 22 CDs, a separate template was created to represent the current clinical, pathological and genetic knowledge of the disease. In addition, each template contains representative clinical photographs as well as light and electron microscopic images and, if available, confocal microscopic and coherence tomographic images of the respective CD. After the first edition was published in 2008, the revised version followed in 2015. The third edition of the IC3D was published as open access in February 2024. The latest edition is intended to serve as a reference work in everyday clinical practice and facilitate the diagnosis of CD, which might sometimes be difficult. This article provides an overview of the diagnostic and treatment principles of CD and presents the IC3D and its changes over time.
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Introduction: Many loci segregate alleles classified as "genetic diseases" due to their deleterious effects on health. However, some disease alleles have been reported to show beneficial effects under certain conditions or in certain populations. The beneficial effects of these antagonistically pleiotropic alleles may explain their continued prevalence, but the degree to which antagonistic pleiotropy is common or rare is unresolved. We surveyed the medical literature to identify examples of antagonistic pleiotropy to help determine whether antagonistic pleiotropy appears to be rare or common. Results: We identified ten examples of loci with polymorphisms for which the presence of antagonistic pleiotropy is well supported by detailed genetic or epidemiological information in humans. One additional locus was identified for which the supporting evidence comes from animal studies. These examples complement over 20 others reported in other reviews. Discussion: The existence of more than 30 identified antagonistically pleiotropic human disease alleles suggests that this phenomenon may be widespread. This poses important implications for both our understanding of human evolutionary genetics and our approaches to clinical treatment and disease prevention, especially therapies based on genetic modification.
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Together with its ß-subunit OSTM1, ClC-7 performs 2Cl-/H+ exchange across lysosomal membranes. Pathogenic variants in either gene cause lysosome-related pathologies, including osteopetrosis and lysosomal storage. CLCN7 variants can cause recessive or dominant disease. Different variants entail different sets of symptoms. Loss of ClC-7 causes osteopetrosis and mostly neuronal lysosomal storage. A recently reported de novo CLCN7 mutation (p.Tyr715Cys) causes widespread severe lysosome pathology (hypopigmentation, organomegaly, and delayed myelination and development, "HOD syndrome"), but no osteopetrosis. We now describe two additional HOD individuals with the previously described p.Tyr715Cys and a novel p.Lys285Thr mutation, respectively. Both mutations decreased ClC-7 inhibition by PI(3,5)P2 and affected residues lining its binding pocket, and shifted voltage-dependent gating to less positive potentials, an effect partially conferred to WT subunits in WT/mutant heteromers. This shift predicts augmented pH gradient-driven Cl- uptake into vesicles. Overexpressing either mutant induced large lysosome-related vacuoles. This effect depended on Cl-/H+-exchange, as shown using mutants carrying uncoupling mutations. Fibroblasts from the p.Y715C patient also displayed giant vacuoles. This was not observed with p.K285T fibroblasts probably due to residual PI(3,5)P2 sensitivity. The gain of function caused by the shifted voltage-dependence of either mutant likely is the main pathogenic factor. Loss of PI(3,5)P2 inhibition will further increase current amplitudes, but may not be a general feature of HOD. Overactivity of ClC-7 induces pathologically enlarged vacuoles in many tissues, which is distinct from lysosomal storage observed with the loss of ClC-7 function. Osteopetrosis results from a loss of ClC-7, but osteoclasts remain resilient to increased ClC-7 activity.
Subject(s)
Chloride Channels , Lysosomal Storage Diseases , Lysosomes , Humans , Male , Chloride Channels/genetics , Chloride Channels/metabolism , Gain of Function Mutation , HEK293 Cells , Lysosomal Storage Diseases/genetics , Lysosomal Storage Diseases/metabolism , Lysosomal Storage Diseases/pathology , Lysosomes/metabolism , Lysosomes/genetics , Membrane Proteins , Mutation, Missense , Phosphatidylinositol Phosphates/metabolism , Ubiquitin-Protein Ligases , Vacuoles/metabolism , Vacuoles/genetics , Vacuoles/pathologyABSTRACT
There is mounting evidence of the value of clinical genome sequencing (cGS) in individuals with suspected rare genetic disease (RGD), but cGS performance and impact on clinical care in a diverse population drawn from both high-income countries (HICs) and low- and middle-income countries (LMICs) has not been investigated. The iHope program, a philanthropic cGS initiative, established a network of 24 clinical sites in eight countries through which it provided cGS to individuals with signs or symptoms of an RGD and constrained access to molecular testing. A total of 1,004 individuals (median age, 6.5 years; 53.5% male) with diverse ancestral backgrounds (51.8% non-majority European) were assessed from June 2016 to September 2021. The diagnostic yield of cGS was 41.4% (416/1,004), with individuals from LMIC sites 1.7 times more likely to receive a positive test result compared to HIC sites (LMIC 56.5% [195/345] vs. HIC 33.5% [221/659], OR 2.6, 95% CI 1.9-3.4, p < 0.0001). A change in diagnostic evaluation occurred in 76.9% (514/668) of individuals. Change of management, inclusive of specialty referrals, imaging and testing, therapeutic interventions, and palliative care, was reported in 41.4% (285/694) of individuals, which increased to 69.2% (480/694) when genetic counseling and avoidance of additional testing were also included. Individuals from LMIC sites were as likely as their HIC counterparts to experience a change in diagnostic evaluation (OR 6.1, 95% CI 1.1-∞, p = 0.05) and change of management (OR 0.9, 95% CI 0.5-1.3, p = 0.49). Increased access to genomic testing may support diagnostic equity and the reduction of global health care disparities.
Subject(s)
Genetic Testing , Rare Diseases , Whole Genome Sequencing , Humans , Male , Rare Diseases/genetics , Rare Diseases/diagnosis , Female , Child , Genetic Testing/methods , Child, Preschool , Adolescent , Adult , Infant , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/diagnosisABSTRACT
Autophagy phenomenon in the cell maintains proteostasis balance by eliminating damaged organelles and protein aggregates. Imbalance in autophagic flux may cause accumulation of protein aggregates in various neurodegenerative disorders. Regulation of autophagy by either calcium or chaperone play a key role in the removal of protein aggregates from the cell. The neuromuscular rare genetic disorder, GNE Myopathy, is characterized by accumulation of rimmed vacuoles having protein aggregates of ß-amyloid and tau that may result from altered autophagic flux. In the present study, the autophagic flux was deciphered in HEK cell-based model for GNE Myopathy harbouring GNE mutations of Indian origin. The refolding activity of HSP70 chaperone was found to be reduced in GNE mutant cells compared to wild type controls. The autophagic markers LC3II/I ratio was altered with increased number of autophagosome formation in GNE mutant cells compared to wild type cells. The cytosolic calcium levels were also increased in GNE mutant cells of Indian origin. Interestingly, treatment of GNE mutant cells with HSP70 activator, BGP-15, restored the expression and refolding activity of HSP70 along with autophagosome formation. Treatment with calcium chelator, BAPTA-AM restored the cytoplasmic calcium levels and autophagosome formation but not LC3II/I ratio significantly. Our study provides insights towards GNE mutation specific response for autophagy regulation and opens up a therapeutic advancement area in calcium signalling and HSP70 function for GNE related Myopathy.
Subject(s)
Autophagy , Calcium , Distal Myopathies , HSP70 Heat-Shock Proteins , Multienzyme Complexes , Mutation , Humans , Autophagy/genetics , Autophagy/drug effects , Mutation/genetics , Calcium/metabolism , Distal Myopathies/genetics , Distal Myopathies/metabolism , Distal Myopathies/pathology , HSP70 Heat-Shock Proteins/genetics , HSP70 Heat-Shock Proteins/metabolism , Multienzyme Complexes/genetics , Multienzyme Complexes/metabolism , HEK293 Cells , Autophagosomes/metabolism , Autophagosomes/drug effects , IndiaABSTRACT
Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)-associated enzyme-CAS holds great promise for treating many uncured human diseases and illnesses by precisely correcting harmful point mutations and disrupting disease-causing genes. The recent Food and Drug Association (FDA) approval of the first CRISPR-based gene therapy for sickle cell anemia marks the beginning of a new era in gene editing. However, delivering CRISPR specifically into diseased cells in vivo is a significant challenge and an area of intense research. The identification of new CRISPR/Cas variants, particularly ultra-compact CAS systems with robust gene editing activities, paves the way for the low-capacity delivery vectors to be used in gene therapies. CRISPR/Cas technology has evolved beyond editing DNA to cover a wide spectrum of functionalities, including RNA targeting, disease diagnosis, transcriptional/epigenetic regulation, chromatin imaging, high-throughput screening, and new disease modeling. CRISPR/Cas can be used to engineer B-cells to produce potent antibodies for more effective vaccines and enhance CAR T-cells for the more precise and efficient targeting of tumor cells. However, CRISPR/Cas technology has challenges, including off-target effects, toxicity, immune responses, and inadequate tissue-specific delivery. Overcoming these challenges necessitates the development of a more effective and specific CRISPR/Cas delivery system. This entails strategically utilizing specific gRNAs in conjunction with robust CRISPR/Cas variants to mitigate off-target effects. This review seeks to delve into the intricacies of the CRISPR/Cas mechanism, explore progress in gene therapies, evaluate gene delivery systems, highlight limitations, outline necessary precautions, and scrutinize the ethical considerations associated with its application.
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A rare autosomal recessive genetic disease is spinal muscular atrophy with respiratory distress type 1 (SMARD 1; OMIM #604320), which is characterized by progressive distal limb muscle weakness, muscular atrophy, and early onset of respiratory failure. Herein, we report the case of a 4-month-old female infant with SMARD type 1 who was admitted to our hospital owing to unexplained distal limb muscle weakness and early respiratory failure. This report summarizes the characteristics of SMARD type 1 caused by heterozygous variation in the immunoglobulin mu DNA binding protein 2 (IGHMBP2) gene by analyzing its clinical manifestations, genetic variation characteristics, and related examinations, aiming to deepen clinicians' understanding of the disease, assisting pediatricians in providing medical information to parents and improving the decision-making process involved in establishing life support.
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Mitochondria are double membrane-bound organelles the network morphology of which in cells is shaped by opposing events of fusion and fission executed by dynamin-like GTPases. Mutations in these genes can perturb the form and functions of mitochondria in cell and animal models of mitochondrial diseases. An expanding array of chemical, mechanical, and genetic stressors can converge on mitochondrial-shaping proteins and disrupt mitochondrial morphology. In recent years, studies aimed at disentangling the multiple roles of mitochondrial-shaping proteins beyond fission or fusion have provided insights into the homeostatic relevance of mitochondrial morphology. Here, I review the pleiotropy of mitochondrial fusion and fission proteins with the aim of understanding whether mitochondrial morphology is important for cell and tissue physiology.