Cross-Trait Meta-Analysis Reveals a Genetic Link between Inflammation and Aging in Giant Cell Arteritis.

Giant cell arteritis (GCA) is a complex inflammatory disease affecting individuals over 50 suggesting a strong link with aging-related immune and vascular changes. However, the precise mechanisms underlying this age-related susceptibility remain poorly understood. Considering the relevance of aging in GCA, genetic factors influencing biological aging markers, such as telomere shortening and epigenetic age acceleration (EAA), might also contribute to its development.

Unraveling the molecular landscape of Erdheim-Chester disease: new insights from methylome and transcriptome integration.

Erdheim-Chester Disease (ECD) is a rare histiocytosis characterized by a wide spectrum of clinical manifestations. Although somatic mutations have been involved in ECD, its etiology remains poorly understood. This study aimed to identify novel molecular mechanisms involved in ECD through the first integrated methylome and transcriptome analysis.

Genome-wide DNA methylation study reveals specific signatures in the affected arterial tissue of giant cell arteritis patients.

Objectives: Giant cell arteritis (GCA) is a large-vessel vasculitis, potentially causing complications such as blindness and strokes. This study aims to gain insights into the pathogenesis of GCA by identifying specific DNA methylation signatures in the arterial tissue of patients with this vasculitis.

Methods: DNA methylation profiling was analyzed in 79 temporal artery biopsy samples (69 patients with GCA and 10 controls) by performing an epigenome-wide association study (EWAS).

Cross-trait GWAS in COVID-19 and systemic sclerosis reveals novel genes implicated in fibrotic and inflammation pathways.

Objectives: Coronavirus disease 2019 (COVID-19) and SSc share multiple similarities in their clinical manifestations, alterations in immune response and therapeutic options. These resemblances have also been identified in other immune-mediated inflammatory diseases where a common genetic component has been found. Thus, we decided to evaluate for the first time this shared genetic architecture with SSc.

Decoding CD4 T cell transcriptome in giant cell arteritis: Novel pathways and altered cross-talk with monocytes.

Background: Giant cell arteritis (GCA) is an immune-mediated large-vessels vasculitis with complex etiology. Although the pathogenic mechanisms remain poorly understood, a central role for CD4 T cells has been demonstrated. In this context, understanding the transcriptome dysregulation in GCA CD4 T cells will yield new insights into its pathogenesis.

Risk loci involved in giant cell arteritis susceptibility: a genome-wide association study.

Background: Giant cell arteritis is an age-related vasculitis that mainly affects the aorta and its branches in individuals aged 50 years and older. Current options for diagnosis and treatment are scarce, highlighting the need to better understand its underlying pathogenesis. Genome-wide association studies (GWAS) have emerged as a powerful tool for unravelling the pathogenic mechanisms involved in complex diseases.

Sex-specific analysis in Behçet's disease reveals higher genetic risk in male patients.

Objectives: Behçet's disease tends to be more severe in men than women. This study was undertaken to investigate sex-specific genetic effects in Behçet's disease.

Methods: A total of 1762 male and 1216 female patients with Behçet's disease from six diverse populations were studied, with the majority of patients of Turkish origin.

FLT3 functional low-frequency variant rs76428106-C is associated with susceptibility to systemic sclerosis.

Objectives: rs76428106-C, a low frequency polymorphism that affects the splicing of the FLT3 gene, has recently been associated with several seropositive autoimmune diseases. Here, we aimed to evaluate the potential implication of rs76428106-C in the susceptibility to systemic sclerosis (SSc).

Methods: We analysed a total of 26 598 European ancestry individuals, 9063 SSc and 17 535 healthy controls, to test the association between FLT3 rs76428106-C and SSc and its different subphenotypes.

A Summary on the Genetics of Systemic Lupus Erythematosus, Rheumatoid Arthritis, Systemic Sclerosis, and Sjögren's Syndrome.

Systemic lupus erythematosus, systemic sclerosis, rheumatoid arthritis, and Sjögren's syndrome are four major autoimmune rheumatic diseases characterized by the presence of autoantibodies, caused by a dysregulation of the immune system that leads to a wide variety of clinical manifestations. These conditions present complex etiologies strongly influenced by multiple environmental and genetic factors. The human leukocyte antigen (HLA) region was the first locus identified to be associated and still represents the strongest susceptibility factor for each of these conditions, particularly the HLA class II genes, including DQA1, DQB1, and DRB1, but class I genes have also been associated.

Methylome and transcriptome profiling of giant cell arteritis monocytes reveals novel pathways involved in disease pathogenesis and molecular response to glucocorticoids.

Objectives: Giant cell arteritis (GCA) is a complex systemic vasculitis mediated by the interplay between both genetic and epigenetic factors. Monocytes are crucial players of the inflammation occurring in GCA. Therefore, characterisation of the monocyte methylome and transcriptome in GCA would be helpful to better understand disease pathogenesis.

Genetics of Behçet's Disease: Functional Genetic Analysis and Estimating Disease Heritability.

Behçet's disease is a chronic multisystemic inflammatory disorder characterized by recurrent oral and genital ulcers. Although its etiology remains unclear, it is thought that both genetic and environmental factors contribute to the onset and progression of Behçet's disease. Here, we provide an updated view of the genetic landscape and architecture of Behçet's disease.

A longitudinal and transancestral analysis of DNA methylation patterns and disease activity in lupus patients.

Epigenetic dysregulation is implicated in the pathogenesis of lupus. We performed a longitudinal analysis to assess changes in DNA methylation in lupus neutrophils over 4 years of follow-up and across disease activity levels using 229 patient samples. We demonstrate that DNA methylation profiles in lupus are partly determined by ancestry-associated genetic variations and are highly stable over time.

Epigenomics and transcriptomics of systemic sclerosis CD4+ T cells reveal long-range dysregulation of key inflammatory pathways mediated by disease-associated susceptibility loci.

Background: Systemic sclerosis (SSc) is a genetically complex autoimmune disease mediated by the interplay between genetic and epigenetic factors in a multitude of immune cells, with CD4+ T lymphocytes as one of the principle drivers of pathogenesis.

Methods: DNA samples exacted from CD4+ T cells of 48 SSc patients and 16 healthy controls were hybridized on MethylationEPIC BeadChip array. In parallel, gene expression was interrogated by hybridizing total RNA on Clariom™ S array.

The role of a functional variant of TYK2 in vasculitides and infections.

Objectives: The TYK2 gene encodes a tyrosin kinase which is involved in multiple immune functions. A functional variant of this gene has been identified to play a protective role in multiple autoimmune diseases. The goal of this study was to evaluate the involvement of this variant of TYK2 in vasculitides [giant cell arteritis (GCA), ANCA-associated vasculitis (AAV) and IgA vasculitis (IgAV)] and viral infections [hepatitis C virus (HCV) and human immunodeficiency virus type I (HIV-1)].

Genetics of Antiphospholipid Syndrome.

Purpose Of Review: Antiphospholipid syndrome (APS) is a rare heterogenous disorder associated with the presence of antiphospholipid antibodies and can present in a wide variety of clinical manifestations including thrombosis and pregnancy complications. Although the etiology of APS remains poorly understood, there is strong support for considering APS as a complex genetic disease in which multiple genetic risk factors, in conjunction with environmental factors, affect its onset, progression, and severity. Here, we provide a comprehensive review of the current knowledge of the genetic basis of APS, which remains in its infancy.

Monogenic Lupus: A Developing Paradigm of Disease.

Monogenic lupus is a form of systemic lupus erythematosus (SLE) that occurs in patients with a single gene defect. This rare variant of lupus generally presents with early onset severe disease, especially affecting the kidneys and central nervous system. To date, a significant number of genes have been implicated in monogenic lupus, providing valuable insights into a very complex disease process.

Association of a rare variant of the TNFSF13B gene with susceptibility to Rheumatoid Arthritis and Systemic Lupus Erythematosus.

A rare variant (BAFF-var) of the tumor necrosis factor superfamily 13b (TNFSF13B) gene has been recently associated with multiple sclerosis (MS) and systemic lupus erythematosus (SLE). The aim of this study was to investigate the association between TNFSF13B BAFF-var and susceptibility to rheumatoid arthritis (RA) and replicate that association in SLE. 6,218 RA patients, 2,575 SLE patients and 4,403 healthy controls from three different countries were included in the study.

Cross-phenotype analysis of Immunochip data identifies as a relevant for the development of systemic vasculitis.

Objetive: Systemic vasculitides represent a heterogeneous group of rare complex diseases of the blood vessels with a poorly understood aetiology. To investigate the shared genetic component underlying their predisposition, we performed the first cross-phenotype meta-analysis of genetic data from different clinically distinct patterns of vasculitis.

Methods: Immunochip genotyping data from 2465 patients diagnosed with giant cell arteritis, Takayasu's arteritis, antineutrophil cytoplasmic antibody-associated vasculitis or IgA vasculitis as well as 4632 unaffected controls were analysed to identify common susceptibility for vasculitis development.