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Identifying proteomic signatures in treatment-naïve individuals newly diagnosed with inflammatory bowel disease (IBD) may provide insights into the underlying pathophysiological mechanisms of the disease and aid in distinguishing Crohn's disease (CD) from ulcerative colitis (UC). In the discovery phase, label-free quantitative proteomics was performed to analyze proteomic profiles in serum extracellular vesicles (EVs), serum, urine, and intestinal tissue from 100 newly diagnosed IBD patients (50 CD and 50 UC), and 51 healthy controls (HC). Serum candidate biomarkers were validated using ELISA in a separate subset cohort (87 CD, 134 UC, and 99 HC), and immunohistochemistry was performed on biopsies from the discovery cohort to confirm findings. We identified 419 proteins in serum EVs, 468 in serum, 683 in urine, and 2603 in intestinal tissue. ELISA results showed lower levels of TTR and APOC3 and higher levels of ATRN in UC patients compared to HC. Similarly, CD patients showed lower TTR and higher ATRN levels compared to HC. Moreover, serum protein S10A9 was differentially upregulated in CD vs UC. Immunohistochemistry revealed increased PRDX4 and AZU1 expression in the ileum of CD patients, whereas AOFB expression was lower in the ileum of CD and in the left colon of both CD and UC compared to HC. This comprehensive proteomic study has identified a set of proteins differentially expressed in IBD, which may contribute to a better understanding of its mechanisms and hold promise as candidate biomarkers. Although these findings are preliminary, they warrant further investigation to evaluate their diagnostic and therapeutic relevance. Show less

The 17q21.31 region with various structural forms characterized by the H1/H2 haplotypes and three large copy number variations (CNVs) represents the strongest risk locus in progressive supranuclear palsy (PSP). To investigate the association between CNVs and structural forms on 17q.21.31 with the risk of PSP. Utilizing whole genome sequencing data from 1684 PSP cases and 2392 controls, the three large CNVs (α, β, and γ) and structural forms within 17q21.31 were identified and analyzed for their association with PSP. We found that the copy number of γ was associated with increased PSP risk (odds ratio [OR] = 1.10, P = 0.0018). From H1β1γ1 (OR = 1.21) and H1β2γ1 (OR = 1.24) to H1β1γ4 (OR = 1.57), structural forms of H1 with additional copies of γ displayed a higher risk for PSP. The frequency of the risk sub-haplotype H1c rises from 1% in individuals with two γ copies to 88% in those with eight copies. Additionally, γ duplication up-regulates expression of ARL17B, LRRC37A/LRRC37A2, and NSFP1, while down-regulating KANSL1. Single-nucleus RNA-seq of the dorsolateral prefrontal cortex analysis reveals γ duplication primarily up-regulates LRRC37A/LRRC37A2 in neuronal cells. The copy number of γ is associated with the risk of PSP after adjusting for H1/H2, indicating that the complex structure at 17q21.31 is an important consideration when evaluating the genetic risk of PSP. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. Show less

To assess the role of rare copy number variations in Alzheimer's disease (AD), we conducted a case-control study using whole-exome sequencing data from 522 early-onset cases and 584 controls. The most recurrent rearrangement was a 17q21.31 microduplication, overlapping the CRHR1, MAPT, STH and KANSL1 genes that was found in four cases, including one de novo rearrangement, and was absent in controls. The increased MAPT gene dosage led to a 1.6-1.9-fold expression of the MAPT messenger RNA. Clinical signs, neuroimaging and cerebrospinal fluid biomarker profiles were consistent with an AD diagnosis in MAPT duplication carriers. However, amyloid positon emission tomography (PET) imaging, performed in three patients, was negative. Analysis of an additional case with neuropathological examination confirmed that the MAPT duplication causes a complex tauopathy, including prominent neurofibrillary tangle pathology in the medial temporal lobe without amyloid-β deposits. 17q21.31 duplication is the genetic basis of a novel entity marked by prominent tauopathy, leading to early-onset dementia with an AD clinical phenotype. This entity could account for a proportion of probable AD cases with negative amyloid PET imaging recently identified in large clinical series. Show less