Disease Phenotype Research Articles

Pathogenesis of mtDNA point mutation m.10191T>C affecting complex I function is a multifactorial process leading to metabolic remodeling of mitochondria.

Microbiome signatures and their role in uveitis: Pathogenesis, diagnostics, and therapeutic perspectives.

To explore the clinical and genetic characteristics of two children diagnosed with two rare genetic diseases simultaneously. Two children with comorbidity of two genetic diseases due to dual genetic mutations diagnosed at the Third Affiliated Hospital of Zhengzhou University respectively in May 2022 and March 2023 were selected as the study subjects. Clinical and genetic data of the two children were retrospectively analyzed. This study has been approved by the Ethics Committee of the Third Affiliated Hospital of Zhengzhou University (Ethic No. 2021-062-01). Child 1 was a 2-year-and-4-month-old boy whose clinical manifestations included facial dysmorphism, developmental delay, short stature, microcephaly, cleft palate, cryptorchidism, hypospadias, recurrent infections and immunological abnormalities. Whole exome sequencing revealed that he had harbored a heterozygous c.6595delT (p.Y2199Ifs*65) variant of the KMT2D gene and a heterozygous c.1892G>A (p.R631Q) variant of the PIK3R1 gene. This has led to a dual genetic diagnosis of Kabuki syndrome and PI3Kδ-related immunodeficiency type 36. Child 2 was a 15-year-old girl whose clinical manifestations included epilepsy, Albright's hereditary osteodystrophy, long body trunk, short limbs, hypocalcemia, hyperphosphatemia and hyperparathyroidism. The child also had a family history of short stature. Whole exome sequencing revealed that she had harbored a heterozygous c.2T>C (p.Met1?) variant of the GNAS gene and deletion of exons 2 to 6 of the SHOX gene. The two variants have led to dual diagnose of pseudohypoparathyroidism and X-linked idiopathic short stature. When the clinical phenotype of a genetic disease is complex and cannot be fully explained with a single genetic variant, multiple pathogenic variants should be considered, and this may lead to the diagnosis of co-morbid genetic diseases. To adopt or supplement corresponding genetic testing in time and re-analyze the genetic data may facilitate accurate diagnosis of co-morbid genetic diseases.

Primary ciliary dyskinesia (PCD) is a rare genetic respiratory disorder caused by a reduction in cilia number or cilia dysmotility. Cilia dysmotility leads to breathing difficulties, concurrent infections and severe lung damage if not treated, with no therapies currently available. Improved airway epithelial cell models that mimic the disease phenotype are required for development of new therapeutics, as current models have limited potential of self-renewal in vitro. Here, we describe a human PCD cell model created by lentiviral transduction of airway basal epithelial cells with the BMI1 gene, a regulator of senescence. We report that the cells retain their proliferation and differentiation capacity for at least 19 passages and recapitulate the disease phenotype with immotile cilia lacking DNAH5 and other outer dynein arm proteins. Characterisation of the ion transport properties of these PCD cells grown at an air-liquid interface showed lower activity of the Na+ channel ENaC and enhanced CFTR activity compared to non-PCD cells, which might be linked to ciliary immotility. Our study provides a robust PCD model for therapeutic studies, opening new avenues to investigate the molecular mechanisms of this disease.

Progressive Fibrosing Interstitial Lung Disease (PF-ILD) is a severe phenotype of Interstitial Lung Disease (ILD) with a poor prognosis, typically requiring prolonged clinical observation and multiple CT examinations for diagnosis. Such requirements delay early detection and treatment initiation. To enable earlier identification of PF-ILD, we propose ILD-Slider, a parameter-efficient and lightweight deep learning framework that enables accurate PF-ILD identification from a limited number of CT slices. ILD-Slider introduces anatomy-based position markers (PMs) to guide the selection of representative slices (RSs). A PM extractor, trained via a multi-class classification model, achieves high PM detection accuracy despite severe class imbalance by leveraging a peak slice mining (PSM)-based strategy. Using the PM extractor, we automatically select three, five, or nine RSs per case, substantially reducing computational cost while maintaining diagnostic accuracy. The selected RSs are then processed by a slice-level 3D Adapter (Slider) for PF-ILD identification. Experiments on 613 cases from The University of Osaka Hospital (UOH) and the National Hospital Organization Osaka Toneyama Medical Center (OTMC) demonstrate the effectiveness of ILD-Slider, achieving an AUPRC of 0.790 (AUROC 0.847) using only five automatically extracted RSs. ILD-Slider further validates the feasibility of diagnosing PF-ILD from non-contiguous slices, which is particularly valuable for real-world and public datasets where contiguous volumes are often unavailable. These results highlight ILD-Slider as a practical and efficient solution for early PF-ILD identification.

The human blood proteome provides a holistic readout of health states through the assessment of thousands of circulating proteins. Here, we present a pan-disease resource to enable the study of diverse disease phenotypes within a harmonized proteomics dataset. By profiling protein concentrations across 59 diseases and healthy cohorts, we identified proteins associated with age, sex, and BMI, as well as disease-specific signatures. This study highlights shared and distinct protein patterns across conditions, demonstrating the power of a unified proteomics approach to uncover biological insights. The dataset, covering 8,262 individuals and up to 5,416 proteins, serves as an online resource for exploring disease-specific protein profiles and advancing precision medicine research.

Coagulation factor (F) VII deficiency is the most frequent among the rare, inherited bleeding disorders and is predominantly caused by missense mutations in the F7 gene. The disease phenotype ranges from asymptomatic cases to extremely severe hemorrhagic forms, requiring prophylactic injections with plasma-derived or recombinant FVII concentrates. In response, we have developed an autologous cell-based approach that corrects the disease-causing mutation in patient-derived induced pluripotent stem cells (iPSCs) and generates therapeutic, three-dimensional hepatic organoids (HOs). We report the CRISPRmediated correction of homozygous c.718G>C (p.G240R), a missense mutation associated with a severe, life-threatening bleeding phenotype. The HOs contain all liver cell types and exhibit key liver functions, including coagulation factor production. After correction, our data indicate that the patient-derived HOs secrete consistent amounts of functional FVII protein, resulting in improved thrombin generation times. These results represent a significant milestone toward the establishment of an autologous cell-based therapy for patients with FVII- and other coagulation factor deficiencies.

Infiltration of T cells into the kidney of Dahl salt-sensitive (SS) rats accompanies SS hypertension and renal damage. Genetic deletion of T cells on the SS background (knockout of the CD247 gene in Dahl salt-sensitive rat [SSCD247-/-]) attenuates hypertension and renal damage, and adoptive transfer of T cells restores the disease phenotype in an NOX2 (NADPH oxidase 2)-dependent manner. This study aimed to identify the specific T-cell subtype involved in the amplification of Dahl SS hypertension. Adoptive transfer of purified CD (cluster of differentiation) 4+ or CD8+ T cells isolated from SS rats or from rats with a genetic deletion of a subunit of NOX2 was performed into the SSCD247-/-. A negative control group received PBS vehicle. After 3 weeks of a high-salt (4.0% NaCl) diet, rats receiving CD4+ T cells from the SS demonstrated amplified SS hypertension and albuminuria compared with all other groups, including the rats that received CD4+ T cells lacking functional NOX2. No differences were observed in rats receiving CD8+ T cells. Flow cytometric analysis documented equal reconstitution of CD3+ cells in the adoptive transfer rats. A gene expression analysis demonstrated upregulation of inflammatory genes in the CD4+ cells in the kidney of the SS rats compared with the T cells of rats lacking functional NOX2. Subsequent experiments documented a positive correlation between CD4+ T cells in diseased human kidneys and renal damage, providing a translational aspect to this study. In summary, these studies indicate that CD4+ T cells amplify SS hypertension and renal damage in the Dahl SS rats via an NOX2-dependent mechanism.

Given the limitations of current IBD treatments, this study conducted an in-depth investigation of 17 human-derived Bifidobacterium longum subsp. longum strains. Primary screening using a lipopolysaccharide (LPS)-induced RAW264.7 macrophage inflammation model identified strain F05-044-CM-09 as exhibiting significantly stronger inhibition of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α) production compared to other strains. To explore the genetic basis of its anti-inflammatory effect, strain-specific gene analysis revealed that F05-044-CM-09 harbors a gene encoding the CHAP domain, suggesting that anti-inflammatory efficacy may involve immunomodulation through dendritic cell activation and interleukin-2 (IL-2) production. A safety assessment performed prior to animal experiments confirmed the absence of virulence genes and genes encoding D-lactate production. In a dextran sulfate sodium (DSS)-induced murine colitis model, F05-044-CM-09 intervention significantly ameliorated disease phenotypes by mitigating body weight loss and colon shortening, restoring colonic gland architecture, and reducing inflammatory cell infiltration. Analysis of serum biomarkers showed that F05-044-CM-09 significantly reduced LPS levels, whereas serum TNF-α levels showed a decreasing trend that was not statistically significant. However, colonic TNF-α concentrations were significantly reduced following F05-044-CM-09 intervention. In summary, F05-044-CM-09 has the potential to alleviate enteritis and a good safety profile. It is a promising candidate for the development of anti-inflammatory probiotics and offers new possibilities for IBD treatment.

BackgroundEpicardial adipose tissue (EAT) plays an important role in the pathogenesis of coronary artery disease (CAD). The association between EAT and obstructive CAD or myocardial ischemia has been established, but its relationship with CAD phenotypes based on anatomical and functional imaging remains unclear.MethodsA total of 495 suspected CAD patients who underwent both single-photon emission computed tomography/computed tomography myocardial perfusion imaging (SPECT/CT MPI) and coronary angiography (CAG/CTA) were enrolled in this retrospective study. Epicardial fat volume (EFV) and epicardial fat volume indexed to body surface (EFVi) were measured on non-contrast CT. CAD phenotypes were categorized into 4 groups based on the presence or absence of obstructive CAD (any epicardial coronary diameter stenosis ≥ 50% by CAG/CTA) and myocardial ischemia (diagnosed by MPI): Group1 (non-obstructive CAD without ischemia, n = 165), Group2 (ischemia with non-obstructive CAD, INOCA, n = 69), Group3 (obstructive CAD without ischemia, n = 149), Group4 (obstructive CAD with ischemia, n = 112).ResultsBoth EFV and EFVi had an increasing trend across 4 groups [EFVi: median (interquartile range), cm3/m2: 80.54 (68.10-102.37) vs. 84.44 (73.57-100.93) vs. 89.63 (75.39-103.15) vs. 91.67 (76.48-111.66), p = 0.007, p for trend < 0.001]. In adjusted ordered logistic regression model, EFVi was independently associated with more advanced CAD phenotype levels (per SD unit change: OR = 1.26, 95% CI:1.03–1.55, p = 0.024). Subgroup analysis showed diabetes subgroup had the strongest correlation between EFVi and CAD phenotype levels in ordered logistic regression model (OR = 3.45, 95%CI:1.52–7.82, p = 0.003). In adjusted unordered multinomial logistic regression model, with Group1 as reference group, maximizing Youden index method was used to find the optimal cutoff values for EFV/EFVi on Group2 to Group4. Both EFV and EFVi were independently associated with Group3 and Group4 but only EFVi was independently associated with INOCA (EFV: EFV >134.47cm3 for INOCA, OR = 1.94, 95%CI:0.97–3.88, p = 0.058, EFVi: EFVi >80.67cm3/m2 for INOCA, OR = 2.53, 95%CI:1.25–5.12, p = 0.010). Net reclassification improvement (NRI) showed that EFVi was more effective than EFV in diabetes subgroup to differentiate CAD phenotypes over traditional cardiovascular risk factors.ConclusionEFVi was correlated with the severity of CAD phenotype levels based on anatomical and functional imaging. EFVi had the strongest correlation with CAD phenotypes levels in diabetes subgroup. Notably, EFVi rather than EFV exhibits a distinct linkage with INOCA. EFVi was more effective to provide incremental value of differentiating CAD phenotypes over traditional cardiovascular risk factors than EFV in diabetes subgroup.Graphical Supplementary InformationThe online version contains supplementary material available at 10.1186/s12933-025-02897-0.

Years before diagnosis of Parkinson disease (PD), dementia with Lewy bodies (DLB), or multiple system atrophy (MSA), mild prodromal manifestations can be detected. Longitudinal follow-up of people with prodromal synucleinopathy, particularly idiopathic/isolated REM sleep behavior disorder (iRBD), enables in-depth clinical phenotyping of early disease, which could facilitate stratification for clinical trials, provide the definition of appropriate end points, or predict phenoconversion more precisely. The aim of this study was to update and expand on previous studies assessing clinical evolution from iRBD to clinically diagnosed disease, up to 14 years before diagnosis. People with polysomnography-proven iRBD were included in this prospective cohort study (2004-2023) at Center for Advanced Research in Sleep Medicine (Montreal). Participants were followed annually with comprehensive motor and nonmotor assessments until they fulfilled clinical diagnostic criteria for PD, DLB, or MSA ("phenoconversion"). Tracing backward from phenoconversion, clinical trajectories in iRBD were compared with age-expected trajectories, as well as between PD and DLB phenoconverters, using mixed-effects models. A total of 95 people with iRBD were included in the analysis (69.0 ± 8.5 years, 26% female, RBD duration 7.1 ± 7.4 years, follow-up 1-15 years) and were eventually diagnosed with either PD (n = 46), DLB (n = 43), or MSA (n = 6). Among phenoconverters, Movement Disorders Society-Unified Parkinson's Disease Rating Scale Part III and quantitative motor testing showed slowly progressing changes from Y-10, followed by exponential increase approximately 4 years before phenoconversion (F(4,298) = 79.1, p < 0.001). From 4 to 5 years before phenoconversion, accelerated worsening was found in global cognition (F(3,278) = 33.7, p < 0.001) and color vision (F(3,646) = 15.9, p < 0.001). Hyposmia was evident from Y-14 and progressed linearly (F(1,37) = 15.0, p < 0.001). Autonomic manifestations were evident from Y-12. DLB phenoconverters showed faster decline in global cognition (F(3,95) = 21.0, p < 0.001) and color vision (F(3,235) = 3.5, p = 0.02) than PD phenoconverters. Participants with iRBD showed evolving motor and nonmotor impairment many years before diagnosis of manifest synucleinopathy compared with estimated age-expected references. Our results suggest that some clinical features emerge early and progress linearly while others develop gradually and progress more rapidly shortly before phenoconversion. Prodromal PD, MSA, and DLB phenoconverters showed overlapping but distinct clinical trajectories, mainly for motor testing, cognitive function, and color vision. Additional large multicenter studies including longitudinal follow-up of controls are needed.

African men are disproportionately impacted by aggressive prostate cancer (PCa). The key to this disparity is both genetic and environmental factors, alluding to epigenetic modifications. However, African-inclusive prostate tumour DNA methylation studies are lacking. Assembling a multi-geo-ancestral prostate tissue cohort, including men with (57 African, 48 European, 23 Asian) or without (65 African) PCa, we interrogate for genome-wide differential methylation. Overall, methylation appears to be driven by ancestry over geography (152 southern Africa, 41 Australia). African tumours show substantial heterogeneity, with universal hypermethylation indicating more pervasive epigenetic silencing, encompassing PCa suppressor genes and enhancer-targeted binding motifs. Conversely, African tumour-associated heterochromatic hypomethylation suggests chromatin relaxation and developmental pathway activation via enhancer targets. Notably, non-prostate lineage elements appeared preferentially exploited in African tumorigenesis, with ancestry potentially influencing the extent of lineage-inappropriate activation, and tumour progression marked by repression of developmental regulators. Together, these findings point to extensive epigenetic plasticity in African tumours, with intergenic regulatory remodelling promoting genomic instability, metastatic potential and aggressive disease phenotypes.

A typical hypertensive heart disease phenotype is the left ventricular hypertrophy (LVH) and dysfunction, measurable via LV mass and global longitudinal strain. We aimed to evaluate the LV mass-to-strain ratio (LV-MSR) as a marker of the clinical course in patients with hypertensive heart disease. We retrospectively analyzed consecutive patients who underwent echocardiography at the time of hypertension diagnosis and at 6- to 18-month intervals in tertiary centers from 2006 to 2021. Associations of LV-MSR with LVH changes and clinical outcomes (cardiovascular death and heart failure hospitalization occurring after the second echocardiogram) were assessed using time-dependent receiver-operating characteristic analysis and multivariable Cox regression. Among 1600 patients (mean age 65.1 years; 61.1% male), 23.4% had concentric LVH, and 21.5% had eccentric LVH at baseline. The median interval between echocardiograms was 10.2 months (interquartile range, 6.8-13.4). LV-MSR showed the highest discriminatory value for LVH changes (area under the curve, 0.726 [95% CI, 0.685-0.760]), outperforming LV mass index (area under the curve, 0.690 [95% CI 0.648-0.728]; P<0.001) and LV-global longitudinal strain (area under the curve, 0.600 [95% CI 0.558-0.647]; P<0.001). Higher LV-MSR was significantly associated with new-onset LVH (global test P<0.001) and persistent LVH (global test P<0.001). LV-MSR was an independent prognosticator, both as a continuous (adjusted hazard ratio [HR], 1.044 per +1 g/m2 per % [95% CI 1.020-1.069]) or categorical variable (adjusted HR 2.267 for LV-MSR, ≥6.52 g/m2 per % [95% CI 1.520-3.381]). These associations remained consistent across subgroups by sex and baseline LVH status. LV-MSR independently predicts LVH changes and clinical outcomes in hypertensive heart disease, serving as a superior prognostic marker compared with LV mass index or LV-global longitudinal strain alone.

Multiple sclerosis (MS) is a neuroinflammatory and neurodegenerative disorder of the central nervous system (CNS). Age is the strongest predictor of disease phenotype, with the majority of older adults transitioning to a progressive form marked by irreversible neurological decline. This clinical progression is associated with smoldering, CNS-compartmentalized inflammation and neurodegeneration, for which there are currently no effective disease-modifying therapies. Cellular senescence, characterized by the secretion of pro-inflammatory mediators collectively known as the senescence-associated secretory phenotype (SASP), increases with age and contributes to tissue injury. In MS, neuroinflammation can further promote cellular senescence, creating a self-reinforcing cycle of damage. Senescent microglia have been identified within MS lesions, where their SASP may impair remyelination and exacerbate neurodegeneration. Senolytic agents selectively target and eliminate senescent cells by disrupting anti-apoptotic pathways. In experimental autoimmune encephalomyelitis (EAE), a widely used model of MS, senolytic treatment reduces senescent microglia burden and attenuates disease severity in an age- and drug-dependent manner. Specifically, here we show that middle-aged mice (40–44 weeks) with EAE exhibit improved clinical outcomes and survival following treatment with either dasatinib plus quercetin (D+Q) or navitoclax. Early-phase clinical trials of senolytics in age-related diseases have demonstrated functional benefits, including improved gait speed in idiopathic pulmonary fibrosis and CNS penetrance in Alzheimer’s disease. Translating senolytic therapy to MS will require careful selection of CNS-penetrant and well-tolerated agents, identification of appropriate patient populations, and deployment of responsive biomarkers. Senolytic therapy represents a promising geroscience-based strategy to meet the urgent therapeutic need in progressive MS.

BackgroundThe ATP synthase F1 subunit α (ATP5F1A) gene encodes a critical structural subunit of mitochondrial complex V. ATP5F1A mutations are linked to mitochondrial complex V deficiency diseases. Although only 14 cases have been reported globally, the genotype-phenotype correlations and underlying molecular mechanisms remain poorly understood.ObjectiveTo investigate the pathogenic mechanisms of ATP5F1A deficiency through functional analysis of a recurrent missense variant.MethodA Han Chinese family with developmental delay and motor dysfunction was studied. Whole-exome sequencing and trio analysis identified the causative variant. Pathogenicity was evaluated using bioinformatic predictions and structural modeling. HEK293T cells were transfected with wild-type or mutant-type ATP5F1A plasmids for Western blot and immunofluorescence analysis. Morpholino (MO) oligonucleotides were microinjected into zebrafish embryos for gene knockdown. Motor neuron development was observed in Tg(mnx1:eGFP) zebrafish, with accompanying behavioral assessments. RNA sequencing was conducted to explore the underlying molecular pathways.ResultsA de novo missense variant (c.1252G > A, p.Gly418Arg) in ATP5F1A was identified and shown to segregate with the disease phenotype. The mutation reduced protein stability and expression. In HEK293T cells, the mutant protein exhibited reduced expression without affecting mitochondrial localization. In zebrafish, atp5fa1 knockdown caused growth retardation, motor dysfunction, and impaired motor neuron axon development. Rescue experiments with human wild-type ATP5F1A mRNA partially restored motor neuron morphology. Transcriptomic analysis identified 2,261 differentially expressed genes, enriched in neurotransmission and apelin signaling pathways. qPCR confirmed downregulation of autophagy-related genes (apln, becn1, map1lc3b) in knockdown larvae. Western blot showed that atp5fa1 knockdown increased P62 and decreased Lc3b-II expression in zebrafish models.ConclusionThis study is the first to report pathogenic ATP5F1A mutations in the Chinese population. Atp5fa1 dysfunction leads to multi-system defects and disease phenotypes in a zebrafish model, possibly mediated through inhibiting autophagy activation mechanisms.

The expression of the genetic components involved in quantitative disease resistance (QDR) are often not well understood and analyses of genotype-by-genotype interactions can shed light on how the resistance and the activation of resistance strategies vary across interactions. To deepen the knowledge on QDR and the molecular interactions in the Norway spruce (Picea abies)- Heterobasidion annosum s.l.. pathosystem we inoculated ten relatively resistant spruce clones with four H. annosum s.s. isolates with varying virulence and determined the disease phenotypes. Thereafter we analysed the transcriptome in nine interactions between three spruce clones and three isolates. We tested the hypotheses that (i) differences among host and pathogen genotypes affect the disease symptoms; (ii) host genotypes respond differently depending on the isolate they were challenged with and (iii) this effect is accompanied by distinct transcriptional reprogramming. We found varying levels of disease expression among the interactions influenced by both host and pathogen genotypes. The host genotype was the strongest predictor of the disease phenotype, especially early in the interaction. The transcriptional responses differed between the three clones, interactions resulting in longer necrotic lesions were associated with larger numbers of differentially expressed genes. Despite this and the strong impact of the host genotype on disease phenotype each interaction displayed distinct transcriptional responses in a host genotype. These results indicate that phenotypic resistance responses can be governed by different defence modules and genes in Norway spruce. For instance, several leucine rich repeat family genes were found to be upregulated in the clones with higher resistance and downregulated in the clone with the lower resistance indicating that recognition of the pathogen may be one of the keys to limiting H. annosum s.s. spread in Norway spruce.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12870-025-07438-1.

BackgroundCam morphology is associated with acetabular cartilage lesions and early-onset osteoarthritis in patients with femoroacetabular impingement syndrome. Here, we propose a novel iterative rabbit model of cam morphology to characterize the pathophysiology of femoroacetabular impingement-related cartilage lesions.MethodsWe described a repeatable method for establishing a New Zealand white rabbit model of cam morphology by interfering with the epiphyseal tubercle and evaluated the histological outcomes of acetabular cartilage lesions. Cam morphology and subchondral bone were evaluated by micro-CT scanning. The expression of anabolic and catabolic biomarkers of acetabular cartilage was investigated via western blotting and immunohistochemical staining. Chondrocyte apoptosis was detected via TUNEL staining. Kinematics of the hip joint in the sagittal plane were evaluated by a passive optical motion capture system.ResultsThere were remarkable pathological similarities between this model and human diseases. The cam morphology rabbit model exhibited early cartilage degeneration and subsequent phenotypes of hip osteoarthritis, and this pathological process is not affected by surgical trauma. Hip motion in the cam morphology models resembled that in the healthy controls, and had only a slightly lower joint angle at all phases of the half-bounding gait cycle. This model preserved the natural and predictable movement pattern.ConclusionsThis rabbit model of cam morphology replicates the disease phenotype and allows for scientifically sound evaluation of disease mechanisms. It can be employed to study human cam-type femoroacetabular impingement syndrome.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12891-025-09194-7.

Pathological aggregation of α-synuclein into amyloid fibrils is a hallmark of synucleinopathies, including Parkinson's disease. Despite this commonality, synucleinopathies display divergent disease phenotypes that have been attributed to disease-specific three-dimensional structures of α-synuclein fibrils, each with unique toxic gain-of-function profiles. The Hsc70 chaperone is remarkable in its ability to disassemble pre-existing amyloid fibrils of different proteins in an ATP and co-chaperone-dependent manner. We find, however, using six well-defined conformational polymorphs of α-synuclein fibrils, that the activity of the Hsc70 disaggregase machinery is sensitive to differences in the amyloid conformation, confirming that fibril polymorphism directly affects interactions with the proteostasis network. Amyloid conformation influences not only how efficiently fibrils are cleared by the Hsc70 machinery but also the balance between depolymerization and fragmentation during disaggregation. We further show that, in vitro, the active processing of fibrils by the Hsc70 machinery inadvertently produces seeding competent species that further promote protein aggregation. Amyloid conformation thus is an important feature that can tilt the balance between beneficial or detrimental protein quality control activities in a disease-context.

Genetic testing for 21-hydroxylase deficiency (21OHD) is advantageous when hormonal testing is equivocal, to molecularly confirm diagnosis, and for genetic counseling. To characterize the clinical and biochemical phenotype across the genotypic spectrum of 21OHD in a large cohort using updated genetic methodology. Retrospective study of 457 individuals with 21OHD enrolled in a Natural History study at the NIH Clinical Center. The majority (79%) were compound heterozygous, 46% with chimeric alleles/30-kb deletions including 2.6% with attenuated chimeras, 10.1% with CAH-X (33% with cardiac defects) and 3.7% with genotype-phenotype discordance. The most common mutations among individuals with salt-wasting (SW), simple-virilizing (SV), and nonclassic (NC) phenotypes were In2G, I172N, and V281L respectively. Rare or novel mutations accounted for 4.3% alleles, 0.33% arose de novo. 17OHP levels at diagnosis varied by genotype group (Null>In2G> SV genotypes > P30L > Other NC; P<0.001); but maximum values obtained during clinical care over time were similar among all classic and among all NC genotypes. Individuals with P30L had higher 17OHP and lower cortisol at diagnosis compared to other NC genotypes (P<0.001) and were more likely to have basal 17OHP >1,000ng/dL (P<0.001). Individuals with cryptic NC had lower 17OHP post cosyntropin stimulation compared to those with symptomatic NC (P=0.02). A continuum of disease phenotypes exists with biochemical overlap that increases with age. Improving genotype accuracy to include chimera subtyping to identify attenuated chimeras and CAH-X and consideration of P30L as a unique group are important to guide genetic counseling and provide anticipatory guidance in disease management.

Oral intake of n (omega)-3 polyunsaturated fatty acids (PUFAs) is associated with changes to gut microbiota. We review recent findings from 2024 onwards, which build the scientific case that changes to bacterial abundance, and their metabolites, contribute to the health benefits associated with n-3 PUFAs. There are now multiple studies in rodent disease models that demonstrate that n-3 PUFAs do not significantly alter bacterial diversity but, instead, alter abundance of several species that are implicated in short-chain fatty acid synthesis, in a model-specific manner. Limited intervention studies in humans, backed by larger observational studies, concur with the preclinical findings. Importantly, faecal transplantation experiments have confirmed that n-3 PUFA-induced changes to gut microbiota are causally related to reversal of the disease phenotype in two rodent models. In-vitro colonic models are now being used to understand the mechanism(s) underlying n-3 PUFA-induced changes to the gut microbiota and metabolome. Despite emerging proof that the gut microbiota contributes to n-3 PUFA activity in animal models, human data are sparse. It remains unclear how n-3 PUFAs affect changes to the gut microbiota or whether n-3 PUFA metabolism by gut microbes contributes to the host metabolome.