OBJECTIVES: The gut microbiota plays a crucial role in the pathophysiology of various types of diabetes. However, the causal relationship between them has yet to be systematically elucidated. This study aims to explore the potential causal associations between gut microbiota and diabetes using a two-sample Mendelian randomization (MR) analysis, based on multiple taxonomic levels. METHODS: Eligible instrumental variables were extracted from the selected genome-wide association study (GWAS) data on gut microbiota. These were combined with GWAS datasets on type 1 diabetes (T1D), type 2 diabetes (T2D), and gestational diabetes mellitus (GDM) to conduct forward MR analysis, sensitivity analysis, reverse MR analysis, and validation of significant estimates. Microbial taxa with causal effects on T1D, T2D, and GDM were identified based on a comprehensive assessment of all analytical stages. RESULTS: A total of 2 179, 2 176, and 2 166 single nucleotide polymorphisms (SNP) were included in the MR analyses for gut microbiota with T1D, T2D, and GDM, respectively. MR results indicated causal associations between: Six microbial taxa (Eggerthella, Lachnospira, Bacillales, Desulfovibrionales, Parasutterella, and Turicibacter) and T1D; 9 microbial taxa (Verrucomicrobia, Deltaproteobacteria, Actinomycetales, Desulfovibrionale, Actinomycetaceae, Desulfovibrionaceae, Actinomyces, Alcaligenaceae, and Lachnospiraceae NC2004 group) and T2D; 10 microbial taxa (Betaproteobacteria, Coprobacter, Ruminococcus2, Tenericutes, Clostridia, Methanobacteria, Mollicutes, Methanobacteriales, Methanobacteriaceae, and Methanobrevibacter) and GDM. CONCLUSIONS This study identified specific gut microbial taxa that may significantly increase or decrease the risk of developing diabetes. Some findings were fully replicated in independent validation datasets. However, the underlying biological mechanisms of these causal relationships warrant further investigation through mechanistic studies and population-based research.
Gastrointestinal Microbiome/genetics* ; Humans ; Mendelian Randomization Analysis ; Genome-Wide Association Study ; Diabetes Mellitus, Type 2/genetics* ; Diabetes Mellitus, Type 1/genetics* ; Female ; Polymorphism, Single Nucleotide ; Diabetes, Gestational/genetics* ; Pregnancy

OBJECTIVES: Keloids are fibrotic skin disorders characterized by excessive collagen deposition and a high recurrence rate, closely associated with inflammatory mediators. However, existing epidemiological studies are limited by confounding factors and reverse causality, making it difficult to establish causation. This study aims to investigate the causal relationship between circulating cytokines and keloids using Mendelian randomization analysis. METHODS: Significant single nucleotide polymorphisms (SNPs) associated with circulating cytokines (exposures) and keloids (outcomes) were extracted from genome-wide association study (GWAS) summary datasets. Eligible SNPs were selected as instrumental variables (IVs). Exposure data were derived from a cytokine GWAS including 8 293 Finnish participants, and outcome data from a keloid GWAS based on the UK Biobank. The inverse-variance weighted (IVW) method served as the primary analytical approach to estimate causal effects, supplemented by weighted median (WME), MR-Egger regression, and other sensitivity analyses. Horizontal pleiotropy was assessed using MR-Egger regression and the MR pleiotropy residual sum and outlier (MR-PRESSO) test, while Cochran's Q test evaluated heterogeneity. Leave-one-out analysis was used to verify robustness and consistency. A reverse MR analysis was also conducted, with keloid as the exposure and cytokines as outcomes, to rule out reverse causation. RESULTS: IVW analysis identified significant positive causal associations between two cytokines and keloids-macrophage migration inhibitory factor (MIF) [odds ratio (OR)=2.081, 95% confidence interval (CI) 1.219 to 3.552, P=0.007] and monocyte chemoattractant protein-1 (MCP-1) (OR=1.673, 95% CI 1.036 to 2.701, P=0.035). Conversely, stem cell factor (SCF) showed a negative causal relationship with keloids (OR=0.518, 95% CI 0.269 to 0.998, P=0.049). Results from the MR-Egger and weighted median analyses were consistent with IVW findings. No evidence of horizontal pleiotropy was observed (P>0.05). Except for interleukin-6 (P=0.014), no heterogeneity was detected in other cytokines. Leave-one-out analysis further confirmed the robustness of the causal associations. In reverse MR analysis, keloids were causally related only to β-nerve growth factor (beta-NGF) (OR=1.048, 95% CI 1.002 to 1.095, P=0.039), with no heterogeneity or pleiotropy detected in most cytokines (P>0.05). CONCLUSIONS MIF and MCP-1 exhibit positive causal associations with keloid formation, while SCF shows a negative causal relationship. These findings provide new evidence for the causal involvement of inflammatory cytokines in keloid pathogenesis and offer potential molecular targets for developing novel keloid therapies.
Humans ; Keloid/blood* ; Mendelian Randomization Analysis ; Cytokines/genetics* ; Polymorphism, Single Nucleotide ; Genome-Wide Association Study ; Chemokine CCL2/genetics* ; Interleukin-6/genetics* ; Macrophage Migration-Inhibitory Factors/genetics* ; Male ; Stem Cell Factor/blood* ; Female ; Intramolecular Oxidoreductases

In this study, we employed a combination of genome mining and heteronuclear single quantum coherence (HSQC)-based small molecule accurate recognition technology (SMART) technology to search for fernane-type triterpenoids. Initially, potential endophytic fungi were identified through genome mining. Subsequently, fine fractions containing various fernane-type triterpenoids were selected using HSQC data collection and SMART prediction. These triterpenoids were then obtained through targeted isolation and identification. Finally, their antifungal activity was evaluated. As a result, three fernane-type triterpenoids, including two novel compounds, along with two new sesquiterpenes and four known compounds were isolated from one potential strain, Diaporthe discoidispora. Their structures were elucidated through analysis of high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and nuclear magnetic resonance (NMR) spectroscopic data. The absolute configurations were determined using single-crystal X-ray diffraction analysis and electron capture detector (ECD) analysis. Compound 3 exhibited moderate antifungal activity against Candida albicans CMCC 98001 and Aspergillus niger.
Triterpenes/isolation & purification* ; Antifungal Agents/isolation & purification* ; Molecular Structure ; Candida albicans/drug effects* ; Ascomycota/genetics* ; Magnetic Resonance Spectroscopy ; Aspergillus niger/drug effects* ; Genome, Fungal ; Microbial Sensitivity Tests

OBJECTIVE: Several epidemiological observational studies have related particulate matter (PM) exposure to Inflammatory bowel disease (IBD), but many confounding factors make it difficult to draw causal links from observational studies. The objective of this study was to explore the causal association between PM _2.5 exposure, its absorbance, and IBD. METHODS: We assessed the association of PM _2.5 and PM _2.5 absorbance with the two primary forms of IBD (Crohn's disease [CD] and ulcerative colitis [UC]) using Mendelian randomization (MR) to explore the causal relationship. We conducted two-sample MR analyses with aggregated data from the UK Biobank genome-wide association study. Single-nucleotide polymorphisms linked with PM _2.5 concentrations or their absorbance were used as instrumental variables (IVs). We used inverse variance weighting (IVW) as the primary analytical approach and four other standard methods as supplementary analyses for quality control. RESULTS: The results of MR demonstrated that PM _2.5 had an adverse influence on UC risk (odds ratio [ OR] = 1.010; 95% confidence interval [ CI] = 1.001-1.019, P = 0.020). Meanwhile, the results of IVW showed that PM _2.5 absorbance was also causally associated with UC ( OR = 1.012; 95% CI = 1.004-1.019, P = 0.002). We observed no causal relationship between PM _2.5, PM _2.5 absorbance, and CD. The results of sensitivity analysis indicated the absence of heterogeneity or pleiotropy, ensuring the reliability of MR results. CONCLUSION Based on two-sample MR analyses, there are potential positive causal relationships between PM _2.5, PM _2.5 absorbance, and UC.
Humans ; Mendelian Randomization Analysis ; Particulate Matter/analysis* ; Polymorphism, Single Nucleotide ; Inflammatory Bowel Diseases/genetics* ; Air Pollutants/analysis* ; Crohn Disease/genetics* ; Colitis, Ulcerative/genetics* ; Genome-Wide Association Study ; Risk Factors ; Environmental Exposure

OBJECTIVE: To re-analyze a likely pathogenic variant in the Xq28 region identified by copy number variation sequencing (CNV-seq) through whole genome sequencing (WGS). METHODS: A fetus found to harbor a duplication in the Xq28 region by CNV-seq at Shengjing Hospital Affiliated to China Medical University in May 2023 was selected as the study subject. WGS was carried out for the fetus and its parents. Bioinformatic software was used to analyze the chromosomal structure and CNVs. Quantitative PCR (qPCR) was applied to determine the expression level of the MECP2 gene. This study has been approved by the Ethics Committee of Shengjing Hospital (Ethic No. 2013PS33K). RESULTS: A duplication (ChrX:153302641_153503563) and four breakpoints were identified on the X chromosome of the fetus' father. Bioinformatic analysis revealed that the duplicated region has involved exons 1 to 3 and part of the 5'-UTR of the MECP2 gene, which was inserted into the Xp11 region. Additionally, an inversion was detected in the Xp11 region adjacent to the duplicated segment. RT-PCR results showed normal level of MECP2 mRNA expression. The Xq28 duplication has not encompassed the entire MECP2 gene, nor disrupted its structure or altered its expression. CONCLUSION WGS has enabled more precise diagnosis of chromosomal structural variants and provided guidance for accurate genetic counseling for the affected families.
Humans ; Female ; Chromosomes, Human, X/genetics* ; DNA Copy Number Variations/genetics* ; Whole Genome Sequencing/methods* ; Methyl-CpG-Binding Protein 2/genetics* ; Pregnancy ; Male ; Adult

OBJECTIVE: To explore the genetic etiology of a Chinese pedigree with recurrent Joubert syndrome with negative results by whole-exome sequencing in the prior proband. METHODS: Chinese pedigree which opted elective abortion at the Women and Children's Hospital Affiliated to Chongqing Medical University in December 2024 was selected as the study subject. Whole-genome sequencing was carried out on fetal tissue after termination of pregnancy. Candidate variants were validated by Sanger sequencing and interpreted, while non-coding variant was analyzed using in silico prediction tools. RNA sequencing and cDNA sequencing were conducted on fetal brain tissue. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.2024YL045-02). RESULTS: Both the fetus and the affected child were found to harbor compound heterozygous variants of the CEP290 gene, namely c.7341dup (p.Leu2448fs*8) (pathogenic, maternally inherited) and c.1523-408G>A (likely pathogenic, paternally inherited). Both in silico analysis and fetal brain RNA sequencing confirmed aberrant RNA splicing caused by the intronic variant. CONCLUSION This case has highlighted the value of combining whole-genome sequencing with RNA functional validation. Above results not only enriched the spectrum of CEP290 gene mutations but also underscored its diagnostic value in resolving complex prenatal cases, providing critical clues for the prenatal diagnosis and recurrence risk assessment in genetic counseling.
Female ; Humans ; Pregnancy ; Abnormalities, Multiple/genetics* ; Antigens, Neoplasm/genetics* ; Cell Cycle Proteins/genetics* ; Cerebellum/abnormalities* ; Cytoskeletal Proteins/genetics* ; Eye Abnormalities/genetics* ; Introns/genetics* ; Kidney Diseases, Cystic/diagnosis* ; Pedigree ; Retina/abnormalities* ; Sequence Analysis, RNA/methods* ; Whole Genome Sequencing/methods* ; Child

OBJECTIVE: To explore the genetic characteristics and pathogenesis for a child with mosaicism trisomy 21 and Congenital leukemia (CL). METHODS: A child who was admitted to Ningbo Women and Children's Hospital in March 2023 was selected as the study subject. A retrospective analysis was carried out on the clinical data, laboratory test results, immunophenotyping, and genetic characteristics of the child. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: EC2024-063). RESULTS: Whole genome sequencing (WGS) revealed that the child has mosaicism trisomy of chromosome 21, with a ratio of approximately 74%. In addition, copy number variations involving multiple OMIM genes that could explain his clinical phenotype were detected and rated as pathogenic based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). No pathogenic variant was detected with the GATA1 gene. Blood immune typing of the child conformed to the immunophenotype of acute myeloid leukemia. CONCLUSION For children with trisomy 21, even in the absence of GATA1 gene variants, the occurrence of CL should be monitored, and early diagnosis and treatment are of great significance for improving the prognosis.
Child, Preschool ; Humans ; DNA Copy Number Variations/genetics* ; Down Syndrome/genetics* ; GATA1 Transcription Factor/genetics* ; Leukemia/congenital* ; Mosaicism ; Mutation ; Retrospective Studies ; Whole Genome Sequencing

The exploration of pathogenic single nucleotide polymorphisms in the genome plays a pivotal role in the study of human disease-associated genetic mutations. However, there remains a lack of suitable high-throughput screening platforms to investigate the impact of point mutations on genomic structure and function. CRISPR/Cas9-mediated base editors has enabled large-scale annotation of the human genome and phenotypic characterization of monogenic disorders. Base editors, a precise gene-editing technique capable of achieving targeted base substitutions, can be employed to induce mutations at specific functional sites, thereby observing their effects on gene expression, protein function, and cellular phenotypes. Furthermore, integrating base editors with high-throughput screening technologies allows for large-scale evaluation of multiple candidate sites, accelerating the identification of functional loci and providing a powerful tool for disease research and therapeutic target discovery. This article aims to introduce the working principles of various base editors, including cytosine base editors, adenine base editors, and prime editors, and summarize recent advances in high-throughput screening of functional genomic sites using base-editing techniques.
Humans ; Gene Editing/methods* ; CRISPR-Cas Systems/genetics* ; Genome, Human ; Polymorphism, Single Nucleotide

The International System for Human Cytogenomic Nomenclature (ISCN) is a standardized international nomenclature system established by the International Standing Committee on Human Cytogenomic Nomenclature (ISCN SC). It is designed for describing chromosomal or genomic abnormalities detected by commonly used genetic and genomic techniques including but not limited to karyotyping, fluorescence in situ hybridization, microarray, genome mapping, various region-specific assays, and high-throughput sequencing. With a history spanning over six decades, the ISCN was revised by the ISCN SC in 2024 and officially published in September 2024. This article provides a summary for the updates introduced in the 2024 edition of the International System for Human Cytogenomic Nomenclature.
Humans ; Terminology as Topic ; Genomics ; Genome, Human/genetics*

OBJECTIVES: This study aimed to investigate the association between temporomandibular disorder (TMD) and insomnia using a two-sample Mendelian randomization (MR) approach. METHODS: Bidirectional MR analyses of two samples, TMD (n=377 277) and insomnia (n=375 359), were performed using genome-wide association study statistics published in the FinnGen database. Instrumental variables were first screened, and then inverse variance weighting (IVW) and MR-Egger were used as the main-effect assessment methods. Weighted median, weighted mode, and simple mode served as supplementary methods. We used IVW and MR-Egger to test for heterogeneity, as well as MR-Egger intercepts to assess the single nucleotide polymorphism (SNP) potential level of multiplicity effects. Sensitivity analyses were conducted based on leave-one-out to identify potentially influential SNPs. All analyses were conducted by using the two-sample MR R package and were considered statistically significant when P<0.05. RESULTS: MR analysis showed the presence of TMD on insomnia (OR=1.089, 95%CI: 1.017-1.166, P=0.014). Meanwhile, no effect of insomnia on TMD (OR=0.996, 95%CI: 0.964-1.029, P=0.816) was found. The sensitivity-analysis showed that no heterogeneity existed (P>0.05), and the presence of horizontal pleiotropy was not detected (P>0.05). Leave-one-out sensitivity analysis showed no single SNP, which may affect the causal relation. All findings indicated that the causal relationship between TMD and insomnia was not significantly affected by any individual SNP and that IV did not bias the results. CONCLUSIONS Results of MR analyses showed that TMD is a risk factor for insomnia, whereas insomnia is not a risk factor for TMD.
Humans ; Sleep Initiation and Maintenance Disorders/genetics* ; Mendelian Randomization Analysis ; Polymorphism, Single Nucleotide ; Temporomandibular Joint Disorders/complications* ; Genome-Wide Association Study