| 1. |
- Franks, P. W., et al.
(author)
-
Technological readiness and implementation of genomic-driven precision medicine for complex diseases
- 2021
-
In: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 290:3, s. 602-620
-
Research review (peer-reviewed)abstract
- The fields of human genetics and genomics have generated considerable knowledge about the mechanistic basis of many diseases. Genomic approaches to diagnosis, prognostication, prevention and treatment - genomic-driven precision medicine (GDPM) - may help optimize medical practice. Here, we provide a comprehensive review of GDPM of complex diseases across major medical specialties. We focus on technological readiness: how rapidly a test can be implemented into health care. Although these areas of medicine are diverse, key similarities exist across almost all areas. Many medical areas have, within their standards of care, at least one GDPM test for a genetic variant of strong effect that aids the identification/diagnosis of a more homogeneous subset within a larger disease group or identifies a subset with different therapeutic requirements. However, for almost all complex diseases, the majority of patients do not carry established single-gene mutations with large effects. Thus, research is underway that seeks to determine the polygenic basis of many complex diseases. Nevertheless, most complex diseases are caused by the interplay of genetic, behavioural and environmental risk factors, which will likely necessitate models for prediction and diagnosis that incorporate genetic and non-genetic data.
|
|
| 2. |
- Assadi, Ghazaleh, et al.
(author)
-
Functional Analyses of the Crohn's Disease Risk Gene LACC1
- 2016
-
In: PLOS ONE. - San Francisco, USA : Public Library of Science. - 1932-6203. ; 11:12
-
Journal article (peer-reviewed)abstract
- Background: Genetic variation in the Laccase (multicopper oxidoreductase) domain-containing 1 (LACC1) gene has been shown to affect the risk of Crohn's disease, leprosy and, more recently, ulcerative colitis and juvenile idiopathic arthritis. LACC1 function appears to promote fatty-acid oxidation, with concomitant inflammasome activation, reactive oxygen species production, and anti-bacterial responses in macrophages. We sought to contribute to elucidating LACC1 biological function by extensive characterization of its expression in human tissues and cells, and through preliminary analyses of the regulatory mechanisms driving such expression.Methods: We implemented Western blot, quantitative real-time PCR, immunofluorescence microscopy, and flow cytometry analyses to investigate fatty acid metabolism-immune nexus (FAMIN; the LACC1 encoded protein) expression in subcellular compartments, cell lines and relevant human tissues. Gene-set enrichment analyses were performed to initially investigate modulatory mechanisms of LACC1 expression. A small-interference RNA knockdown in vitro model system was used to study the effect of FAMIN depletion on peroxisome function.Results: FAMIN expression was detected in macrophage-differentiated THP-1 cells and several human tissues, being highest in neutrophils, monocytes/macrophages, myeloid and plasmacytoid dendritic cells among peripheral blood cells. Subcellular co-localization was exclusively confined to peroxisomes, with some additional positivity for organelle endomembrane structures. LACC1 co-expression signatures were enriched for genes involved in peroxisome proliferator-activated receptors (PPAR) signaling pathways, and PPAR ligands downregulated FAMIN expression in in vitro model systems.Conclusion: FAMIN is a peroxisome-associated protein with primary role(s) in macrophages and other immune cells, where its metabolic functions may be modulated by PPAR signaling events. However, the precise molecular mechanisms through which FAMIN exerts its biological effects in immune cells remain to be elucidated.
|
|
| 3. |
- Kaminsky, Zachary A., et al.
(author)
-
DNA methylation profiles in monozygotic and dizygotic twins
- 2009
-
In: Nature Genetics. - : Nature Publishing Group. - 1061-4036 .- 1546-1718. ; 41:2, s. 240-245
-
Journal article (peer-reviewed)abstract
- Twin studies have provided the basis for genetic and epidemiological studies in human complex traits. As epigenetic factors can contribute to phenotypic outcomes, we conducted a DNA methylation analysis in white blood cells (WBC), buccal epithelial cells and gut biopsies of 114 monozygotic (MZ) twins as well as WBC and buccal epithelial cells of 80 dizygotic (DZ) twins using 12K CpG island microarrays. Here we provide the first annotation of epigenetic metastability of approximately 6,000 unique genomic regions in MZ twins. An intraclass correlation (ICC)-based comparison of matched MZ and DZ twins showed significantly higher epigenetic difference in buccal cells of DZ co-twins (P = 1.2 x 10(-294)). Although such higher epigenetic discordance in DZ twins can result from DNA sequence differences, our in silico SNP analyses and animal studies favor the hypothesis that it is due to epigenomic differences in the zygotes, suggesting that molecular mechanisms of heritability may not be limited to DNA sequence differences.
|
|
| 4. |
- Fransén, Karin, 1973-, et al.
(author)
-
Polymorphism in the retinoic acid metabolizing enzyme CYP26B1 and the development of Crohn's disease
- 2013
-
In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:8, s. e72739-
-
Journal article (peer-reviewed)abstract
- Several studies suggest that Vitamin A may be involved in the pathogenesis of inflammatory bowel disease (IBD), but the mechanism is still unknown. Cytochrome P450 26 B1 (CYP26B1) is involved in the degradation of retinoic acid and the polymorphism rs2241057 has an elevated catabolic function of retinoic acid, why we hypothesized that the rs2241057 polymorphism may affect the risk of Crohn's disease (CD) and Ulcerative Colitis (UC). DNA from 1378 IBD patients, divided into 871 patients with CD and 507 with UC, and 1205 healthy controls collected at Örebro University Hospital and Karolinska University Hospital were analyzed for the CYP26B1 rs2241057 polymorphism with TaqMan® SNP Genotyping Assay followed by allelic discrimination analysis. A higher frequency of patients homozygous for the major (T) allele was associated with CD but not UC compared to the frequency found in healthy controls. A significant association between the major allele and non-stricturing, non-penetrating phenotype was evident for CD. However, the observed associations reached borderline significance only, after correcting for multiple testing. We suggest that homozygous carriers of the major (T) allele, relative to homozygous carriers of the minor (C) allele, of the CYP26B1 polymorphism rs2241057 may have an increased risk for the development of CD, which possibly may be due to elevated levels of retinoic acid. Our data may support the role of Vitamin A in the pathophysiology of CD, but the exact mechanisms remain to be elucidated.
|
|
| 5. |
- Zhulina, Yaroslava, 1973-, et al.
(author)
-
Subclinical Inflammation with Increased Neutrophil Activity in Healthy Twin Siblings Reflect Environmental Influence in the Pathogenesis of Inflammatory Bowel Disease
- 2013
-
In: Inflammatory Bowel Diseases. - Philadelphia, USA : Lippincott Williams & Wilkins. - 1078-0998 .- 1536-4844. ; 19:8, s. 1725-1731
-
Journal article (peer-reviewed)abstract
- Background: The mechanisms behind increased fecal calprotectin (FC) in healthy relatives of patients with inflammatory bowel disease (IBD) are unknown. Our aims were to explore if there is a subclinical inflammation with increased neutrophil activity in healthy twin siblings in discordant twin pairs with IBD and to assess the influence of genetics in this context.Methods: Nuclear factor kappa B (NF-B) and neutrophil activity, based on myeloperoxidase (MPO) and FC, were analyzed in healthy twin siblings in discordant twin pairs with IBD and compared with healthy controls. NF-B and MPO were assessed by immunohistochemistry and FC by enzyme-linked immunosorbent assay.Results: In total, 33 of 34 healthy twin siblings were histologically normal. Increased NF-B was more often observed in healthy twin siblings in discordant twin pairs with Crohn's disease (13/18 [73%]) and with ulcerative colitis (12/16 [75%]) than in healthy controls (8/45 [18%]). MPO was more often increased in healthy twin siblings in discordant pairs with Crohn's disease (12/18 [67%]) than in healthy controls (11/45 [24%]) and FC more often in healthy twin siblings in discordant pairs with ulcerative colitis (14/21 [67%]) than in healthy controls (6/31 [19%]). Interestingly, the observed differences remained when healthy monozygotic and dizygotic twin siblings were analyzed separately.Conclusions:We observed increased NF-B, MPO, and FC in healthy twins in both monozygotic and dizygotic discordant pairs with IBD. These novel findings speak for an ongoing subclinical inflammation with increased neutrophil activity in healthy first-degree relatives.
|
|
| 6. |
- Chen, Jie, et al.
(author)
-
Bidirectional Mendelian Randomisation Analysis Provides Evidence for the Causal Involvement of Dysregulation of CXCL9, CCL11 and CASP8 in the Pathogenesis of Ulcerative Colitis
- 2023
-
In: Journal of Crohn's & Colitis. - : Oxford University Press. - 1873-9946 .- 1876-4479. ; 17:5, s. 777-785
-
Journal article (peer-reviewed)abstract
- Background and Aims Systemic inflammation is well recognised to be associated with ulcerative colitis [UC], but whether these effects are causal or consequential remains unclear. We aimed to define potential causal relationship of cytokine dysregulation with different tiers of evidence. Methods We first synthesised serum proteomic profiling data from two multicentred observational studies, in which a panel of systemic inflammatory proteins was analysed to examine their associations with UC risk. To further dissect observed associations, we then performed a bidirectional two-sample Mendelian randomisation [TSMR] analysis from both forward and reverse directions using five genome-wide association study [GWAS] summary level data for serum proteomic profiles and the largest GWAS of 28 738 European-ancestry individuals for UC risk. Results Pooled analysis of serum proteomic data identified 14 proteins to be associated with the risk of UC. Forward MR analysis using only cis-acting protein quantitative trait loci [cis-pQTLs] or trans-pQTLs further validated causal associations of two chemokines and the increased risk of UC: C-X-C motif chemokine ligand 9 [CXCL9] [OR 1.45, 95% CI 1.08, 1.95, p = 0.012] and C-C motif chemokine ligand 11 [CCL11] [OR 1.14, 95% CI 1.09, 1.18, p = 3.89 x 10(-10)]. Using both cis- and trans-acting pQTLs, an association of caspase-8 [CASP8] [OR 1.04, 95% CI 1.03, 1.05, p = 7.63 x 10(-19)] was additionally identified. Reverse MR did not find any influence of genetic predisposition to UC on any of these three inflammation proteins. Conclusion Pre-existing elevated levels of CXCL9, CCL11 and CASP8 may play a role in the pathogenesis of UC.
|
|
| 7. |
- Moraes Holst, Luiza, et al.
(author)
-
Downregulated Mucosal Autophagy, Alpha Kinase-1 and IL-17 Signaling Pathways in Active and Quiescent Ulcerative Colitis
- 2022
-
In: Clinical and Experimental Gastroenterology. - : DOVE MEDICAL PRESS LTD. - 1178-7023. ; 15, s. 129-144
-
Journal article (peer-reviewed)abstract
- Background: Improved mucosal immune profiling in active and quiescent colonic inflammatory bowel disease (IBD) is needed to develop therapeutic options for treating and preventing flares. This study therefore aimed to provide a comprehensive mucosal characterization with emphasis on immunological host response of patients with active ulcerative colitis (UC active), UC during remission (UC remission) and active colonic Crohn's disease (CD active).Methods: Colonic biopsies from 47 study subjects were collected for gene expression and pathway analyses using the NanoString host-response panel, including 776 genes and 56 immune-related pathways.Results: The majority of mucosal gene expression and signaling pathway scores were increased in active IBD (n=27) compared to healthy subjects (n=10). However, both active IBD and UC remission (n=10) demonstrated decreased gene expression and signaling pathway scores related to autophagy, alpha kinase-1 and IL-17 signaling pathways compared to healthy subjects. Further, UC remission was characterized by decreased scores of several signaling pathways linked to homeostasis along with increased mononuclear cell migration pathway score as compared to healthy subjects. No major differences in the colonic mucosal gene expression between CD active (n=7) and UC (n=20) active were observed.Conclusion: This study indicates that autophagy, alpha kinase-1 and IL-17 signaling pathways are persistently downregulated in UC irrespective of disease activity. Further, UC patients in remission present a unique mucosal environment, potentially preventing patients from reaching and sustaining true homeostasis. These findings may enable better comprehension of the remitting and relapsing pattern of colonic IBD and guide future treatment and prevention of flares.
|
|
| 8. |
- Wouters, Mira M., et al.
(author)
-
Genetic variants in CDC42 and NXPH1 as susceptibility factors for constipation and diarrhoea predominant irritable bowel syndrome
- 2014
-
In: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 63:7, s. 1103-1111
-
Journal article (peer-reviewed)abstract
- Objective: The complex genetic aetiology underlying irritable bowel syndrome (IBS) needs to be assessed in large-scale genetic studies. Two independent IBS cohorts were genotyped to assess whether genetic variability in immune, neuronal and barrier integrity genes is associated with IBS.Design: 384 single nucleotide polymorphisms (SNPs) covering 270 genes were genotyped in an exploratory cohort (935 IBS patients, 639 controls). 33 SNPs with P-uncorrected<0.05 were validated in an independent set of 497 patients and 887 controls. Genotype distributions of single SNPs were assessed using an additive genetic model in IBS and clinical subtypes, IBS-C and IBS-D, both in individual and combined cohorts. Trait anxiety (N=614 patients, 533 controls), lifetime depression (N=654 patients, 533 controls) and mRNA expression in rectal biopsies (N=22 patients, 29 controls) were correlated with SNP genotypes.Results: Two SNPs associated independently in the exploratory and validation cohort: rs17837965-CDC42 with IBS-C (ORexploratory=1.59 (1.05 to 1.76); ORvalidation=1.76 (1.03 to 3.01)) and rs2349775-NXPH1 with IBS-D (ORexploratory=1.28 (1.06 to 1.56); ORvalidation=1.42 (1.08 to 1.88)). When combining both cohorts, the association of rs2349775 withstood post hoc correction for multiple testing in the IBS-D subgroup. Additionally, three SNPs in immune-related genes (rs1464510-LPP, rs1881457-IL13, rs2104286-IL2RA), one SNP in a neuronal gene (rs2349775-NXPH1) and two SNPs in epithelial genes (rs245051-SLC26A2, rs17837965-CDC42) were weakly associated with total-IBS (P-uncorrected<0.05). At the functional level, rs1881457 increased IL13 mRNA levels, whereas anxiety and depression scores did not correlate with rs2349775-NXPH1.Conclusions: Rs2349775 (NXPH1) and rs17837965 (CDC42) were associated with IBS-D and IBS-C, respectively, in two independent cohorts. Further studies are warranted to validate our findings and to determine the mechanisms underlying IBS pathophysiology.
|
|
| 9. |
- Drobin, Kimi, et al.
(author)
-
Targeted Analysis of Serum Proteins Encoded at Known Inflammatory Bowel Disease Risk Loci
- 2019
-
In: Inflammatory Bowel Diseases. - : Oxford University Press. - 1078-0998 .- 1536-4844. ; 25:2, s. 306-316
-
Journal article (peer-reviewed)abstract
- Background: Few studies have investigated the blood proteome of inflammatory bowel disease (IBD). We characterized the serum abundance of proteins encoded at 163 known IBD risk loci and tested these proteins for their biomarker discovery potential.Methods: Based on the Human Protein Atlas (HPA) antibody availability, 218 proteins from genes mapping at 163 IBD risk loci were selected. Targeted serum protein profiles from 49 Crohn's disease (CD) patients, 51 ulcerative colitis (UC) patients, and 50 sex- and age-matched healthy individuals were obtained using multiplexed antibody suspension bead array assays. Differences in relative serum abundance levels between disease groups and controls were examined. Replication was attempted for CD-UC comparisons (including disease subtypes) by including 64 additional patients (33 CD and 31 UC). Antibodies targeting a potentially novel risk protein were validated by paired antibodies, Western blot, immuno-capture mass spectrometry, and epitope mapping.Results: By univariate analysis, 13 proteins mostly related to neutrophil, T-cell, and B-cell activation and function were differentially expressed in IBD patients vs healthy controls, 3 in CD patients vs healthy controls and 2 in UC patients vs healthy controls (q < 0.01). Multivariate analyses further differentiated disease groups from healthy controls and CD subtypes from UC (P < 0.05). Extended characterization of an antibody targeting a novel, discriminative serum marker, the laccase (multicopper oxidoreductase) domain containing 1 (LACC1) protein, provided evidence for antibody on-target specificity.Conclusions: Using affinity proteomics, we identified a set of IBD-associated serum proteins encoded at IBD risk loci. These candidate proteins hold the potential to be exploited as diagnostic biomarkers of IBD.
|
|
| 10. |
- Assadi, G., et al.
(author)
-
LACC1 polymorphisms in inflammatory bowel disease and juvenile idiopathic arthritis
- 2016
-
In: Genes and Immunity. - : Nature Publishing Group. - 1466-4879 .- 1476-5470. ; 17:4, s. 261-264
-
Journal article (peer-reviewed)abstract
- The function of the Laccase domain-containing 1 (LACC1) gene is unknown, but genetic variation at this locus has been reported to consistently affect the risk of Crohn's disease (CD) and leprosy. Recently, a LACC1 missense mutation was found in patients suffering from monogenic forms of CD, but also systemic juvenile idiopathic arthritis. We tested the hypothesis that LACC1 single nucleotide polymorphisms (SNPs), in addition to CD, are associated with juvenile idiopathic arthritis (JIA, non-systemic), and another major form of inflammatory bowel disease, ulcerative colitis (UC). We selected 11 LACC1 tagging SNPs, and tested their effect on disease risk in 3855 Swedish individuals from three case-control cohorts of CD, UC and JIA. We detected false discovery rate corrected significant associations with individual markers in all three cohorts, thereby expanding previous results for CD also to UC and JIA. LACC1's link to several inflammatory diseases suggests a key role in the human immune system and justifies further characterization of its function(s).
|
|
