Search Results (36)

Background/Objectives: Pharmacogenetics examines genome variability and its influence on drug efficacy and toxicity, forming the foundation for personalized medicine. Patients with inflammatory bowel disease (IBD) treated with azathioprine with thiopurine S-methyltransferase (TPMT) deficiency are at an increased risk of drug-related toxic effects. Variability in the HLA-DQA1 and DQB1 alleles may lead to an inadequate therapeutic response. This study aimed to determine the significance of TPMT and HLA-DQ Allelic Variants in therapy optimization planning. Methods: A retrospective study was conducted to determine TPMT gene polymorphism and the presence of HLA-DQA1 and HLA-DQB1 alleles in children diagnosed with IBD and treated at the Institute for Child and Youth Health Care of Vojvodina in May 2023. Results: The study included 104 children with a mean age of 13.71 ± 3.1 years, with a balanced gender distribution. A TPMT mutation was identified in only one child. The most common HLA-DQA1 alleles were *01 (49%) and *05 (28.8%), while the most frequent allele at the HLA-DQB1 locus was 03 (15.4%). The presence of the HLA-DQA105 allele was associated with the development of anti-drug antibodies against anti-TNF therapy (RR: 1.23; 95% CI: 1.03–1.50), while the presence of HLA-DQA101 was significantly more frequent in children on optimized therapeutic regimens (RR: 1.63; 95% CI: 1.13–2.10). Conclusions: Prior to the initiation of azathioprine therapy, TPMT genotyping should be performed to prevent adverse effects and ensure optimal drug dosing. Identification of the HLA-DQA105 and HLA-DQA101 alleles plays an important role in the planning of biological therapy regimens, including decisions on dose escalation or interval shortening. Full article

With primary membranous nephropathy (pMN), the genetic background is not precisely known. Certain HLA-DQ serotypes however like HLA-DQ 2.5, and single-nucleotide polymorphisms (SNPs) in the phospholipase A2 receptor 1 (PLA2R1) gene pose a risk for the development of pMN. As antigen presentation is linked to a 3-dimensional conformation of the HLA-DQA/DQB dimer, we thought that the specific HLA-DQ haplotype combinations might also be risk factors in the evolution of MN. The HLA-DQ haplotype combinations and the PLA2R1 gene risk variant (rs4664308) genotypes were examined in 67 patients with MN (52 primary, 15 secondary [sMN]) and 77 controls. Based on the presence or absence of PLA2R1 risk alleles, we used a scoring system to assess the risk and to identify protective HLA-DQ haplotype combinations. The HLA-DQ 2.5 serotype was significantly enriched in both pMN and sMN patients compared to the controls. The pMN group had a significantly higher frequency of the PLA2R1 risk allele compared to the sMN group and the controls. HLA-DQ 2.5 appeared to carry the highest risk for the development of pMN, while HLA-DQ 7.5 and 6.2 seemed to be protective. Our results indicate that the HLA-DQ 2.5 probably carries the highest risk in both pMN and sMN, suggesting that this serotype has less specificity for antigens, and it induces an autoimmune response. Here, PLA2R1 played a role in the development of pMN but not in sMN. Full article

Background/Objectives: Inflammatory bowel diseases (IBDs) comprise a group of chronic idiopathic disorders, including ulcerative colitis (UC), Crohn’s disease (CD), and indeterminate colitis (IC). Complex genetic factors, in addition to environmental triggers, have been shown to play a fundamental role in the pathogenesis of IBD, contributing to disease susceptibility. The transition of adolescents with inflammatory bowel disease (IBD) to adult care represents a significant challenge for patients, their families, and healthcare providers. Approximately 25% of individuals with IBD receive a diagnosis before the age of 16, and this population is at increased risk for adverse clinical outcomes. As a result, the transition of care has garnered substantial attention in the scientific and clinical communities over the past decade. This study aims to analyze a cohort of pediatric Sardinian patients with IBD to assess clinical characteristics at diagnosis and at the time of transition and determine potential correlations between NOD2/CARD15 gene variants and HLA class II with the disease phenotype. Methods: From January 2014 to August 2024, we performed an observational, cross-sectional study that included pediatric patients with IBD enrolled in the only pediatric IBD reference center in Sardinia. Data were obtained from the patients’ medical records and from a questionnaire administered at the inclusion visit. In addition, we genotyped a portion of our cohort for the Leu1007fsinsC (SNP13), Gly908Arg (SNP12), and Arg702Trp (SNP8) variants of the NOD2/CARD15 gene, as well as for HLA-DRB1, -DQA1, and -DQB1 class II genes. The obtained results were compared with pediatric data from the national epidemiological IBD registry and existing literature. Results: Seventy-one IBD patients were enrolled (UC 43, CD 28, M 34, F 37). Median age at diagnosis was 12.2 years (IQR 2–17). After a median disease duration of 5 years (IQR: 1–16), only three UC patients experienced proximal extension of proctitis or left-sided colitis, and no CD patients experienced new localizations of disease. Fifteen patients developed extraintestinal manifestations. No significant difference was found in median diagnostic delay (DD) between UC [4 months (IQR: 1–84)] and CD patients [4.5 months (IQR: 1–48)]. At the transition visit, overall, twenty-nine patients (42%) were exposed to one biologic agent (vs. 3% at baseline; p < 0.02); 3 patients (4%) were exposed to two or more biologic agents. 7% of patients (5/71) underwent surgery. By comparing the distribution of NOD2/CARD15 SNPs between pediatric patients and an adult CD population, we found a significant association between gene allelic variants and pediatric onset (p = 0.00048). Our study also revealed a statistically significant association between Sardinian pediatric patients carrying NOD2/CARD15 mutations and early-onset CD (p < 0.009492), along with a stenosing phenotype (p < 0.024) and increased surgical risk (p < 0.026). No significant associations were observed between HLA class II alleles and IBD in our population. Conclusions: Our results provide important insights into the clinical and epidemiological features of the pediatric IBD population. In addition, our study highlights the significant role of NOD2/CARD15 gene polymorphisms in pediatric onset CD. These variants influence the age of onset and disease phenotype, characterized by greater severity and a higher risk of surgical intervention in pediatric patients. Full article

Background: Colonic diverticulosis is a common condition, particularly in the elderly population. While dietary habits, obesity, smoking, and physical inactivity contribute to its pathogenesis, emerging evidence highlights a genetic predisposition affecting extracellular matrix (ECM) remodeling, inflammation, and connective tissue integrity. The aim of this systematic review was to summarize genetic determinants of colonic diverticulosis. Methods: The PubMed^® database was searched for original studies in humans. The inclusion criteria were named genetic factor and confirmed diverticulosis. Patients with diverticulitis and diverticular diseases were excluded from this review. Results: Out of 137 publications, 10 articles met the inclusion criteria: six large association studies (GWAS) and four cross-sectional studies. The genes regulating ECM turnover, including TIMP1, MMP3, and MMP9, are involved in diverticulosis development. The TIMP1 (rs4898) T allele has been associated with increased susceptibility, potentially due to its role in ECM remodeling. Similarly, MMP3 (rs3025058) and MMP9 (rs3918242) polymorphisms contribute to altered collagen degradation. The COL3A1 (rs3134646) variant coding modified collagen type III may promote diverticular formation. Other genes, such as ARHGAP15 (rs4662344, rs6736741), affect cytoskeletal dynamics. Identified in GWAS studies, gene candidates may be grouped into blood group and immune system-related genes (ABO, HLA-DQA1, HLA-H, OAS1, TNFSF13, FADD), extracellular matrix and connective tissue genes (COL6A1, COLQ, EFEMP1, ELN, HAS2, TIMP2), signaling and cell communication (BMPR1B, WNT4, RHOU, PHGR1, PCSK5), nervous system and neurodevelopment (BDNF, CACNB2, GPR158, SIRT1, SCAPER, TRPS1), metabolism and transporters (SLC25A28, SLC35F3, RBKS, PPP1R14A, PPP1R16B), lipids and cholesterol (LDAH, LYPLAL1, STARD13), transcription and gene regulation (ZBTB4, UBTF, TNRC6B), apoptosis (FADD, PIAS1), and poorly characterized genes (C1TNF7, ENSG00000224849, ENSG00000251283, LINC01082, DISP2, SNX24, THEM4, UBL4B, UNC50, WDR70, SREK1IP1). Conclusions: There are a number of gene variants that probably predispose to colonic diverticulosis. Detailed characterization of the multigene background of diverticulosis will enable appropriate therapeutic or preventive interventions in the future. Full article

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, responsible for Coronavirus Disease 2019 (COVID-19), exhibits a spectrum of clinical manifestations, ranging from asymptomatic to severe pulmonary dysfunction or death. The variability in COVID-19 severity has largely been attributed to the host’s genetic characteristics, suggesting a polygenic genetic architecture, without significant strong evidence of sex-related genetic differences. In this Italian retrospective case–control study, we investigated the association between COVID-19 severity (severe vs. asymptomatic/oligosymptomatic healed individuals) and HLA gene variants, analyzed by next-generation sequencing (NGS). We identified significant HLA alleles (according to the conventional nomenclature), SNPs and haplotypes in the HLA-B, -C, -F, -DQA1, -DRB1, and -DRB5 genes associated with COVID-19 severity. Interestingly, these variants showed biological sex-related effects. Also, we identified specific haplotypes associated with COVID-19 severity that are shared by different conventional HLA alleles, indicated here as “super-haplotypes”. These haplotypes had a biological sex-specific impact on disease severity and markedly increased the risk of severe COVID-19 compared to the conventional HLA alleles (odds ratio of up to 15). Our data suggest that the revision of the current HLA nomenclature may help to identify variants with a stronger effect on disease susceptibility and that association studies could benefit from the stratification of patients by biological sex. If replicated in other disease models, these findings could help to define the functional diversity in immune response between sexes, also based on the HLA system. Finally, due to the global pandemic’s mortality rate, we hypothesize here that SARS-CoV-2 may have acted as a natural selection trigger, leading to a drift in HLA allelic frequencies in the general population. Full article

Autoimmune diseases are among the most prevalent diseases across the world with genetic and environmental factors that contribute to their etiology. Because the exact causes of autoimmune diseases are largely unknown, a Mendelian randomization (MR) approach is used here to examine the potential causal association between gene expression levels and disease risk across various tissues. Specifically, this study focuses on six autoimmune diseases including Crohn’s disease, ulcerative colitis, rheumatoid arthritis, multiple sclerosis, type 1 diabetes mellitus, and systemic lupus erythematosus. Several of these diseases are currently treatable with immunosuppressants that target specific genes, such as TNF-alpha, IL-23, CD20, and more. In this study, a two-sample MR analysis is performed with multitissue expression quantitative trait loci (eQTLs) and large-scale genome-wide association studies to investigate how gene expression can influence the risk of developing these diseases. Our results show that genes HLA-DQA1/2, HLA-DRB1/6, HLA-DQB2, C4A, CYP21A2, and HLA-DQB1-AS1 have a high causal effect across several diseases and tissues, and almost all of these findings originate from the major histocompatibility complex (MHC) region on Chromosome 6. Our findings support the current knowledge of genes associated with these diseases while also revealing novel genes that can be used for drug therapies in the future. Although several drug therapies currently exist to treat this selection of autoimmune diseases, we provide further insights into the main, common pathways responsible for autoimmune disease pathogenesis and discuss novel genes that lack research focus. Full article

Chronic lymphocytic leukemia (CLL) is a distinct category of lymphoproliferative disorder characterized by the clonal expansion of mature B cells, followed by their accumulation in primary and secondary lymphoid organs. Cluster of differentiation (CD) markers such as CD79b, CD45, CD23, CD22 and CD81 serve as reliable prognostic indicators in CLL as well as the human leukocyte antigen (HLA) with its well-documented associations with various cancers. This study aims to investigate, for the first time, potential connections between HLA typing and CD marker expression in CLL. Although it is one of the most prevalent neoplasms, there is a need for biomarkers that can improve survival. This study included 66 CLL patients and 100 controls, with all samples analyzed using biochemical methods, flow cytometry, and cytomorphology. Next-generation sequencing was performed for HLA typing. The results indicate that several CD markers are statistically associated with different HLA alleles, specifically CD45 with HLA-C*07:01:01; CD79b with HLA-DPA1*02:01:02; CD23 with HLA-B*39:01:01; CD22 with HLA-B*49:01:01, HLA-C*07:01:01, HLA-DPB1*02:01:02, and HLA-DRB1*07:01:01; and CD81 with HLA-DPB1*04:02:01, HLA-DQA1*01:04:01, and HLA-DQB1*05:03:01. In conclusion, this research demonstrates significant statistical links between HLA genes and immunophenotypic markers in CLL patients, shedding new light on the immunological context of CLL. Full article

Genetic diversity is an essential indicator that echoes the natural selection and environmental adaptation of a species. Isolated small populations are vulnerable to genetic drift, inbreeding, and limited gene flow; thus, assessing their genetic diversity is critical in conservation. In this study, we studied the genetic diversity of black-and-white snub-nosed monkeys (Rhinopithecus bieti) using neutral microsatellites and five adaptive major histocompatibility complex (MHC) genes. Two DQA1 alleles, two DQB1 alleles, two DRB1 alleles, two DRB5 alleles, and three DPB1 alleles were isolated from a population. The results indicate that neutral microsatellites demonstrate a high degree of heterozygosity and polymorphism, while adaptive MHC genes display a high degree of heterozygosity and moderate polymorphism. The results also show that balancing selection has prominently influenced the MHC diversity of the species during evolution: (1) significant positive selection is identified at several amino acid sites (primarily at and near antigen-binding sites) of the DRB1, DRB5, and DQB1 genes; (2) phylogenetic analyses display the patterns of trans-species evolution for all MHC loci. This study provides valuable genetic diversity insights into black-and-white snub-nosed monkeys, which dwell at the highest altitude and have experienced the harshest environmental selection of all primates globally since the Pleistocene. Such results provide valuable scientific evidence and a reference for making or amending conservation strategies for this endangered primate species. Full article

This study aimed to clarify the association of HLA Class I and II with dcSSc and lcSSc in Thais. HLA typing for 11 gene loci (Class I: HLA-A, B and C, and Class II [HLA-DR, DP and DQ]) was carried out using the Next Generation DNA Sequencing method (three fields) in 92 Thai patients with systemic sclerosis (55 dcSSc, 37 lcSSc) and 135 healthy controls (HCs). The distribution of HLA alleles in patients with dcSSc and lcSSc was compared. When compared with HCs, the AF of A*24:02:01, A*24:07:01, B*27:04:01 and B*27:06 showed an increasing trend in lcSSc patients without statistical significance. DRB1*15:02:01, DRB5*01:02:01, DQA1*01:01:01, DQB1*05:01:24, DPA1*02:01:01 and DPB1*13:01:01 increased significantly in dcSSc patients. DQB1*05:01:24 and DPB1*13:01:01 also increased significantly in lcSSc patients, but less significantly than in dcSSc patients. The association of DPB1*05:01:01 with lcSSc was significantly protective. HLA-A*24:02:01, B*27:06 and C*03:04:01 formed a three-locus haplotype that also constituted an eight-locus haplotype with DRB1*15:02:01, DQA1*01:01:01, DQB1*05:01:24, DPA1*02:01:01 and DPB1*13:01:01. There was a possibility that HLA Class I would play a role in the pathogenesis of lcSSc, while Class II played more of a role in the dcSSc in Thai patients. Full article

A genome-wide association study of resistance to retained placenta (RETP) using 632,212 Holstein cows and 74,747 SNPs identified 200 additive effects with p-values < 10⁻⁸ on thirteen chromosomes but no dominance effect was statistically significant. The regions of 87.61–88.74 Mb of Chr09 about 1.13 Mb in size had the most significant effect in LOC112448080 and other highly significant effects in CCDC170 and ESR1, and in or near RMND1 and AKAP12. Four non-ESR1 genes in this region were reported to be involved in ESR1 fusions in humans. Chr23 had the largest number of significant effects that peaked in SLC17A1, which was involved in urate metabolism and transport that could contribute to kidney disease. The PKHD1 gene contained seven significant effects and was downstream of another six significant effects. The ACOT13 gene also had a highly significant effect. Both PKHD1 and ACOT13 were associated with kidney disease. Another highly significant effect was upstream of BOLA-DQA2. The KITLG gene of Chr05 that acts in utero in germ cell and neural cell development, and hematopoiesis was upstream of a highly significant effect, contained a significant effect, and was between another two significant effects. The results of this study provided a new understanding of genetic factors underlying RETP in U.S. Holstein cows. Full article

Background: Human leukocyte antigen (HLA) genes are important in many immune processes and contribute to many adverse drug reactions. Whether genetic variations in the HLA region are associated with non-steroid anti-inflammatory drug (NSAID) hypersensitivity remains uncertain. Therefore, the aim of our study was to identify HLA genetic variations in patients with NSAID hypersensitivity in the Taiwanese population. Methods: This hospital-based, retrospective case-control study enrolled 37,156 participants with NSAID exposure from the Taiwan Precision Medicine Initiative (TPMI), who were all genotyped and imputed to fine map HLA typing. Our study assigned 1217 cases to the NSAID allergy group and 12,170 controls to a matched group. Logistic regression analyses were utilized to explore associations between HLA alleles and NSAID hypersensitivity. Results: Overall, 13,387 patients were genotyped for eight major HLA alleles. Allele frequencies were different between the two groups. In the NSAID allergy group, the genotype frequencies of HLA-A*02:01, HLA-A*34:01, and HLA-DQA1*06:01 were found to be markedly elevated compared to the control group, a significance that persisted even after applying the Bonferroni correction. Furthermore, the risk of NSAID allergy demonstrated a significant association with HLA-A*02:01 (OR = 1.29, p < 0.001) and HLA-A*34:01 (OR = 9.90, p = 0.001), in comparison to their respective counterparts. Notably, the genotype frequency of HLA-B*46:01 exhibited a significant increase in the severe allergy group when compared with the mild allergy group. Conclusions: We identified HLA genotypes linked to the onset and severity of NSAID hypersensitivity. Our findings establish a basis for precision prescription in future clinical applications. Full article

IgA nephropathy (IgAN) is an autoimmune disorder which is believed to be non-monogenic. We performed an exome-wide association study of 70 children with IgAN and 637 healthy donors. The HLA allele frequencies were compared between the patients and healthy donors from the bone marrow registry of the Pirogov University. We tested 78,020 gene markers for association and performed functional enrichment analysis and transcription factor binding preference detection. We identified 333 genetic variants, employing three inheritance models. The most significant association with the disorder was observed for rs143409664 (PRAG1) in the case of the additive and dominant models (P_BONF = 1.808 × 10⁻¹⁵ and P_BONF = 1.654 × 10⁻¹⁵, respectively), and for rs13028230 (UBR3) in the case of the recessive model (P_BONF = 1.545 × 10⁻⁹). Enrichment analysis indicated the strongly overrepresented “immune system” and “kidney development” terms. The HLA-DQA1*01:01:01G allele (p = 0.0076; OR, 2.021 [95% CI, 1.322–3.048]) was significantly the most frequent among IgAN patients. Here, we characterized, for the first time, the genetic background of Russian IgAN patients, identifying the risk alleles typical of the population. The most important signals were detected in previously undescribed loci. Full article

Enhancing the immune response through breeding is regarded as an effective strategy for improving animal health, as dairy cattle identified as high immune responders are reported to have a decreased prevalence of economically significant diseases. The identification of differentially expressed genes (DEGs) associated with immune responses might be an effective tool for breeding healthy dairy cattle. In this study, antibody-mediated immune responses (AMIRs) were induced by the immunization of hen egg white lysozyme (HEWL) in six Chinese Holstein dairy bulls divided into high- and low-AMIR groups based on their HEWL antibody level. Then, RNA-seq was applied to explore the transcriptome of peripheral whole blood between the two comparison groups. As a result, several major upregulated and downregulated genes were identified and attributed to the regulation of locomotion, tissue development, immune response, and detoxification. In addition, the result of the KEGG pathway analysis revealed that most DEGs were enriched in pathways related to disease, inflammation, and immune response, including antigen processing and presentation, Staphylococcus aureus infection, intestinal immune network for IgA production, cytokine–cytokine receptor interaction, and complement and coagulation cascades. Moreover, six genes (BOLA-DQA5, C5, CXCL2, HBA, LTF, and COL1A1) were validated using RT-qPCR, which may provide information for genomic selection in breeding programs. These results broaden the knowledge of the immune response mechanism in dairy bulls, which has strong implications for breeding cattle with an enhanced AMIR. Full article

Despite the impressive results obtained with immunotherapy in several cancer types, a significant fraction of patients remains unresponsive to these treatments. In colorectal cancer (CRC), B-RafV600 mutations have been identified in 8–15% of the patients. In this work we interrogated a public dataset to explore the surfaceome of these tumors and found that several genes, such as GP2, CLDN18, AQP5, TM4SF4, NTSR1, VNN1, and CD109, were upregulated. By performing gene set enrichment analysis, we also identified a striking upregulation of genes (CD74, LAG3, HLA-DQB1, HLA-DRB5, HLA-DMA, HLA-DMB, HLA-DPB1, HLA-DRA, HLA-DOA, FCGR2B, HLA-DQA1, HLA-DRB1, and HLA-DPA1) associated with antigen processing and presentation via MHC class II. Likewise, we found a strong correlation between PD1 and PD(L)1 expression and the presence of genes encoding for proteins involved in antigen presentation such as CD74, HLA-DPA1, and LAG3. Furthermore, a similar association was observed for the presence of dendritic cells and macrophages. Finally, a low but positive relationship was observed between tumor mutational burden and neoantigen load. Our findings support the idea that a therapeutic strategy based on the targeting of PD(L)1 together with other receptors also involved in immuno-modulation, such as LAG3, could help to improve current treatments against BRAF-mutated CRC tumors. Full article

SARS-CoV-2, which causes COVID-19, has altered human activities all over the world and has become a global hazard to public health. Despite considerable advancements in pandemic containment techniques, in which vaccination played a key role, COVID-19 remains a global threat, particularly for frail patients and unvaccinated individuals, who may be more susceptible to developing ARDS. Several studies reported that patients with COVID-19-related ARDS who were treated with ECMO had a similar survival rate to those with COVID-19-unrelated ARDS. In order to shed light on the potential mechanisms underlying the COVID-19 infection, we conducted this proof-of-concept study using single-cell V(D)J and gene expression sequencing of B cells to examine the dynamic changes in the transcriptomic BCR repertoire present in patients with COVID-19 at various stages. We compared a recovered and a deceased COVID-19 patient supported by ECMO with one COVID-19-recovered patient who did not receive ECMO treatment and one healthy subject who had never been infected previously. Our analysis revealed a downregulation of FXYD, HLA-DRB1, and RPS20 in memory B cells; MTATP8 and HLA-DQA1 in naïve cells; RPS4Y1 in activated B cells; and IGHV3-73 in plasma cells in COVID-19 patients. We further described an increased ratio of IgA + IgG to IgD + IgM, suggestive of an intensive memory antibody response, in the COVID ECMO D patient. Finally, we assessed a V(D)J rearrangement of heavy chain IgHV3, IGHJ4, and IGHD3/IGHD2 families in COVID-19 patients regardless of the severity of the disease. Full article