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Observations of the seafloor Rayleigh ellipticity contribute to seismic imaging in the ocean. To extract such observables from the arbitrarily oriented ocean–bottom seismometer (OBS) data, we develop an orthogonal-regression-based approach to measure the waveform amplitude ratios of the unoriented horizontal and vertical components. The amplitude ratios are then used to calculate the Rayleigh ellipticity (and the sensor orientation angle). The robustness of our method is verified by applications to both the unoriented OBS data and the well oriented on-land seismic data. As we propose to calculate the Rayleigh ellipticity directly from the unoriented three-component data, the measurement process avoids the complexity arising from the surface wave non-great-circle effects and uncertainties of the OBS sensor orientation angles. Overall the Rayleigh ellipticity measurements from our method are systematically higher than those by conventional analysis and show less uncertainties. Our analyses suggest that the Rayleigh ellipticity curve (14–60 s), which could be retrieved from the raw broad-band OBS data, is effective to constrain the oceanic lithosphere structure, and the accurate measurement of Rayleigh ellipticity curve is important. The potential of seafloor Rayleigh ellipticity for seismic imaging in the ocean is evidenced by a case study of the Japan Basin, the Sea of Japan. Considering the insufficient station coverage in the ocean, the single-station measurement of seafloor Rayleigh ellipticity is of significance for OBS community. [ABSTRACT FROM AUTHOR]

The formation of a new ocean basin provides a unique observational window into the structure and deformation of the oceanic lithosphere. This study offers a detailed 1‐D vertically polarized shear‐wave velocity model of the young Japan Basin by interpreting S receiver functions, seafloor Rayleigh wave ellipticities and phase velocities in a Bayesian trans‐dimensional framework. The models suggest a distinct discontinuity in the mid‐lithosphere. Additional analyses indicate that the upper layer is characterized by strong positive radial anisotropy, while the lower layer is more isotropic. We interpret that the upper layer was formed during the back‐arc opening at 20–15 Ma, where the olivine lattice‐preferred orientation (LPO) fabric induced by passive upwelling contributes to the positive radial anisotropy. The lower, less anisotropic layer may be solidified after the sudden cessation of the opening. Small‐scale convection (SSC) from such a major tectonic event could randomize the LPO enough to weaken radial anisotropy before cooling down the asthenosphere, leaving a radially anisotropic discontinuity in the present‐day mid‐lithosphere. The proposed layered evolution history of the lithosphere beneath the Japan Basin illuminates an important role of the small‐scale convection in modifying the structural fabrics of the asthenosphere in terms of radial anisotropy. Such an SSC‐induced radial anisotropy drop could also occur at the base of the lithosphere in regions with ongoing seafloor spreading and enhance the velocity drop of horizontally polarized shear waves. Thus, the role of SSC is non‐negligible in explaining the sharpness of the Gutenberg discontinuity detected by SS precursors beneath the oceanic lithosphere. Plain Language Summary: The formation of the oceanic lithosphere is associated with a relatively simple mantle convection process called seafloor spreading, but may also be affected by more complex, localized processes such as small‐scale mantle convection. To decipher the evolution history of the lithosphere of the Japan Basin, the Sea of Japan, this study collects earthquake waveforms from broadband ocean‐bottom seismometers and offers a detailed 1‐D seismic structural model beneath the Japan Basin by interpreting the multiple seismological observables in a trans‐dimensional Bayesian framework. Our seismic velocity model and associated analysis reveal that the oceanic lithosphere of the Japan Basin is seismically more complex than expected. The upper and lower parts of the lithosphere show distinct seismic anisotropy properties. We propose a layered evolution model for the lithosphere of the Japan Basin, in which small‐scale convection followed a normal seafloor spreading, and resulted in a structural discontinuity in the present‐day mid‐lithosphere. The proposed model highlights the role of the small‐scale convection in modifying the structural fabrics of the asthenosphere in terms of radial anisotropy. Key Points: We construct detailed 1‐D Vsv models of the Japan Basin by trans‐dimensional inversion of multiple observables extracted from ocean‐bottom seismometers recordsOur analysis reveals a mid‐lithosphere discontinuity arising from strong positive radial anisotropy in the upper lithosphereA layered evolution mode associated with small‐scale convection is proposed for the lithosphere of the Japan Basin [ABSTRACT FROM AUTHOR]

Objective: Antineutrophil cytoplasmic antibody (ANCA) has been reported in patients with infective endocarditis. Whether ANCA is associated with certain characteristics of infective endocarditis is unclear. The principal aim of this study is to investigate the clinical implications of ANCA in infective endocarditis and highlight the diagnostic challenge in ANCA-positive patients with infective endocarditis.Methods: A retrospective study was conducted in a tertiary hospital in China from August 2012 to December 2021. Patients with a diagnosis of infective endocarditis and available ANCA results were included in the study. The clinical and pathological characteristics were compared between ANCA-positive and ANCA-negative patients.Results: A total of 237 patients were included. Forty three (18.1%) were ANCA-positive, predominantly c-ANCA/anti-PR3. Compared to ANCA-negative patients, ANCA-positive patients had longer disease duration (P = .004), more frequent purpura (P = .015), macrohematuria (P = .002), proteinuria (P = .043), acute kidney injury (P = .004), and rapidly progressive glomerulonephritis (P = .010). Histologic findings of 8 patients with infective endocarditis-associated glomerulonephritis were reviewed. Two ANCA-positive patients with infective endocarditis presented with pauci-immune necrotizing and crescentic glomerulonephritis. A total of 18.6% of ANCA-positive patients with infective endocarditis were misdiagnosed as ANCA-associated vasculitis.Conclusions: ANCA is detected in a substantial proportion of patients with infective endocarditis. The presence of ANCA in infective endocarditis is associated with longer disease duration, more frequent purpura, and kidney involvement. ANCA-positive infective endocarditis may mimic ANCA-associated vasculitis, and the differential diagnosis is challenging. Whether ANCA is pathogenic in infective endocarditis-associated small vessel vasculitis requires further study. [ABSTRACT FROM AUTHOR]

Situated in a transition zone between the western and eastern North China Craton (NCC), the central NCC exhibits complex dynamics features. Significant lithosphere thinning is observed beneath the eastern NCC and the northern segment of the central NCC. To study how the crust responses to the distinct lateral variations of the lithospheric mantle, we develop a method for joint inversion of Rayleigh and Love dispersion curves based on a transverse‐isotropic (or radial anisotropy) medium and obtain a 3‐D crustal radial anisotropy model. The results reveal significant heterogeneities along the Cenozoic Fenhe‐Weihe Rift (FWR). In the northern FWR, the discretely distributed lower crust positive anisotropy and upper crust negative anisotropy suggest the rifting is mainly dominated by the active mantle upwelling resulting in the Datong volcanoes. Similarly, the northern segment of the Taihang Mountain is also strongly affected by the magmatic activities and exhibits different anisotropy properties compared to its central‐to‐southern counterpart. Based on the negative anisotropy observed in the middle‐to‐lower crust beneath most parts of the Taihang Mountain, we speculate that a lower‐crust compression model can be applied to the Taihang Mountain, which is totally different to that of the adjacent Bohai Bay Basin. Possibly, the root of the Taihang Mountain is pushed by the westward moving lower crust coupled with the lateral escaping mantle flow beneath the Bohai Bay Basin. The Taihang Mountain and the Bohai Bay Basin are formed in similar tectonic environments, but are deformed in different ways. Key Points: A 3‐D crustal radial anisotropy model of the central North China Craton is builtMantle upwelling dominates the northern Fenhe‐Weihe Rift and northern Taihang MountainCrustal radial anisotropy evidences the lower‐crust compression beneath the southern the Taihang Mountain [ABSTRACT FROM AUTHOR]

Situated in a transition zone between the Ordos basin and the Huabei basin, the Trans-North China Orogen (TNCO), or the central North China Craton, evolved as an extensional orogen during the late Mesozoic to Cenozoic, with Fenhe-Weihe Rift (FWR) developing in it in the Cenozoic. In this study, we construct a high resolution lithospheric model of TNCO by jointly interpreting the broadband surface wave dispersions derived from ambient noise and teleseismic surface wave data. The most significant features of the lithospheric mantle are the two separated low velocity anomalies beneath the northern and southern TNCO respectively. Considering that the Pacific slab subducted to the mantle transition zone with a gap under the Datong volcanic zone, and large-scale low-velocity mantle materials are ascending from the lower mantle through the slab gap, which is evidenced by teleseismic P wave tomography, we propose here that the northern TNCO was affected by the mantle upwelling from the lower mantle. On the contrary, the south TNCO was mainly modified from the dehydration reaction process of the stagnant Pacific slab. In the lower crust, we observe significant low velocities beneath the Datong volcanic field, which are interpreted as the recent magmatic underplating resulted from the ongoing mantle upwelling in the northern TNCO. In addition, the mantle upwelling has dominated the rifting process in the northern segment of the FWR. Although the passive rifting of the FWR propagated from south to north, the north FWR is under an active lithosphere thinning regime now. • High-resolution S wave velocity model of TNCO inverted from broadband Rayleigh wave dispersions. • Different causes for lithospheric LVZs in north and south TNCO and On-going lithospheric modification in the TNCO. • Transition from passive to active rifting in the northern segment of the FWR [ABSTRACT FROM AUTHOR]

The Fenhe‐Weihe Rift (FWR) system is one of the most active rift zones in east China, and plays an important role in the reactivation of the North China Craton. In this work, a high‐resolution 3‐D lithospheric S wave velocity model of the FWR is built by joint inversion of receiver functions and ambient noise. Strong correlation between topography and tectonic features is observed at shallow depths. At great depths, strong heterogeneities are observed along the FWR: (1) high‐velocity anomalies emerge beneath the Weihe and Taiyuan basins in the lower crust; (2) two high‐velocity anomalies are imaged in the uppermost mantle beneath the south to central FWR; and (3) two strong large‐scale, low‐velocity zones are observed beneath the north Trans‐North China Oregon: one is at ~60 km and the other one is much larger with a deeper source. Based on the petrologic properties, geochemical analyses, and seismic images obtained in this work, we propose that the rifting mechanisms between the south and north FWR are different. In the south, the rifting could be mainly caused by the passive effects from the uplift of the Tibetan Plateau, while in the north the rifting is due to the combined effects of the asthenosphere upwelling and the counterclockwise rotation of the Ordos block. The uppermost mantle high‐velocity anomalies underneath the south to central part of the FWR could be the remnants of strong ancient cratonic root, and act as mechanical barriers to block the rifting processes between the south and north FWR. Plain Language Summary: A high‐resolution 3‐D crustal and uppermost mantle model of S wave velocity of the Fenhe‐Weihe Rift (FWR) is based on joint inversions of receiver functions and ambient noise. Two high‐velocity bodies are imaged in the uppermost mantle beneath the south to central FWR, while a large‐scale, low‐velocity zone was located beneath the north Trans‐North China Oregon. Passive rifting in the southern FWR is due to the uplift of the Tibetan Plateau, while rifting in the northern FWR is ascribed to the joint effects of the asthenosphere upwelling and propagation of the rifting from the south. Key Points: A high‐resolution 3‐D lithospheric S wave model of the FWR based on joint inversions of receiver functions and ambient noiseTwo high‐velocity bodies in the uppermost mantle beneath south to central FWR and a large‐scale, low‐velocity zone beneath the north TNCODifferent rifting mechanisms between the south and north FWR deciphered by the 3‐D seismic images in this work and previous evidences [ABSTRACT FROM AUTHOR]

Plateau growth of southeastern Tibet is often understood by applying the end-member conceptual models, such as ductile material flow in the deep crust, and lateral extrusion of coherently deforming or rigid blocks. Though recent studies suggest the local crustal flow and movements of rigid blocks may be compatible in a way, ambiguities still persist in the formation of the gently sloping margin of southeastern Tibet and interactions between the plateau and the outer forelands. Here we present a 3D crustal deformation model in southeastern Tibet and adjacent regions, by summarizing different types of seismic anisotropy measurements including a newly obtained continuous map of uppermost crustal anisotropy, which are derived from observations of the directionally dependent teleseismic Rayleigh wave ellipticity. Layered deformation is observed within the crust beneath the southeastern Tibet Plateau, while the outer foreland shows an overall coherently deforming mode. The conspicuous change of the crustal deformation styles across the southeastern Tibet margin is against the idea that the low topographic gradients of the plateau margin were produced by leakage of ductile deep crust beneath the plateau. We argue that both the crustal flow beneath the plateau interior and lateral extrusion of the outer foreland accommodate the intracontinental convergence at southeastern Tibet. • We present Rayleigh H/V anisotropy maps in the southeastern Tibet Plateau and adjacent regions. • Conspicuous change of the crustal deformation styles across the southeastern Tibet margin is identified. • Crustal flow of the plateau interior and lateral extrusion of the outer foreland both accommodate the plateau expansion. [ABSTRACT FROM AUTHOR]

DNA methylation, which has been investigated extensively recently, has been studied in various human diseases, including cancer, and the analysis of DNA methylation has provided useful biomarkers for diagnosing cancer, monitoring treatment, and predicting the prognosis of cancer. Recently, aberrant DNA methylation has been reported in various neuropsychiatric diseases in both postmortem brains and peripheral blood cells. This review summarizes the current evidence on aberrant DNA methylation in peripheral blood cells from patients with neurodevelopmental, neurodegenerative, and psychiatric disorders, and we propose that DNA methylation could be a novel biomarker for these disorders. [ABSTRACT FROM AUTHOR]

Background: Purpura and glomerulonephritis are typical presentations in IgA vasculitis. Infective endocarditis mimicking IgA vasculitis by presenting with glomerulonephritis and purpura is rarely reported.Methods: We searched for cases with infective endocarditis-associated purpura and glomerulonephritis in a tertiary hospital in China and retrospectively reviewed their clinicopathological features. Differential diagnosis and treatment in patients with infective endocarditis-associated purpura and glomerulonephritis were discussed.Results: A total of 20 cases with infective endocarditis-associated purpura and glomerulonephritis were identified among 548 cases with infective endocarditis in our center during an 8-year period: 7 of the 20 cases (35%) were initially misdiagnosed as IgA vasculitis and 10 cases (50%) presented with left-sided endocarditis caused by Streptococcus viridans. Fever (100%, 20 out of 20), prior valvular deformities (80%, 16 out of 20), cardiac murmur (95%, 19 out of 20), splenomegaly (84%, 16 out of 19), embolism (55%, 11 out of 20), and hypocomplementemia (76%, 13 out of 17) were present in most patients. Crescents and mesangial hypercellularity with or without endothelial hypercellularity were the primary findings on light microscopy, with C3-dominant deposition on immunofluorescence. But IgA-dominant staining was also observed (40%, 2 out of 5). In patients with rapidly progressive glomerulonephritis, patients with complete recovery of renal function had shorter disease duration and higher ratio (67% vs 20%) of immunosuppressive therapy compared with patients with partial recovery.Conclusions: Infective endocarditis-associated glomerulonephritis and purpura can closely mimic IgA vasculitis. Differential diagnosis is challenging, particularly when typical presentations of infective endocarditis are absent. In adults with presentations like IgA vasculitis, infective endocarditis should be evaluated through comprehensive clinical and pathological investigations. Immunosuppressive therapy can be considered in patients with severe glomerulonephritis who do not improve after proper anti-infective therapy. [ABSTRACT FROM AUTHOR]

The convergence between the Eurasian Plate and the Philippine Sea Plate results in rapid uplifting of the Taiwan Orogen. To study the mountain building in Taiwan, we present three transects of shear wave velocity across the Taiwan mountain belt with joint inversion of teleseismic Rayleigh wave H/V ratios and phase velocities derived from ambient noise tomography. The Particle Swarm Optimization algorithm is introduced into the joint inversion and is proved to be an efficient tool in solving the geophysical inverse problems. In determining the H/V ratios, cross-correlation techniques are used to reduce the non-great circle effects of the Rayleigh wave packets and to correct sensor misorientations. The cross-correlation techniques improve the accuracy of the H/V measurements, especially at the short periods. The observed up-to-middle crustal thickening in the central segment of the Central Range suggests lithospheric collision tectonism, whereas the lower crustal thickening in southern segment is proposed to be related to subduction of the Eurasian continental crust. In the north, however, no crust thickening is observed. The variations of the crust architecture along the axis of the Taiwan Orogen favor a close coupling relationship between mountain building and slab interactions in the mantle. Beneath the Central Range, the twist of the fate of the Eurasian continental crust from consumption in the south to collision in the central segment is proposed to be resulted from the slab breakoff beneath central Taiwan. • High-resolution shear wave velocity transects across the Taiwan Island from joint inversion. • Deflection of Rayleigh wave packet from the great-circle path. • Coupling of the mountain building with the subsurface slab interactions in Taiwan. [ABSTRACT FROM AUTHOR]

The closure of an ancient ocean basin via oceanic arc‐continent collision has two subduction styles with opposite polarities, which may proceed via subduction polarity reversal (SPR) or a subduction zone jump (SZJ). Interpreting the geometry or kinematic evolution of ancient collisional zones, especially the original subduction polarity, can be challenging. Here we used 2D thermo‐mechanical modeling to investigate the dynamic evolution process of SPR versus SZJ. Our modeling predicts different structural, topographic, magmatic, and basin histories for SPR and SZJ, which can be compared against, and help interpret, the geologic record past sites of oceanic closure during collisional orogens. Our results match geologic observations of past collisions in Kamchatka, eastern Russia, and the Banda Arc, eastern Indonesia, and thus our results can help effectively decode the evolutionary history of past arc‐continent collisions. Plain Language Summary: Determining the geometry and kinematic evolution of ancient subduction zones that experienced collision with an oceanic island arc can be challenging based on the surface geology along. Such collisions usually result in different dynamical evolution processes, namely subduction polarity reversal (SPR) or a subduction zone jump (SZJ). Here we conducted numerical modeling of oceanic island arcs that collide with a continental margin to explore the dynamic evolution process of different subduction styles. Our results reveal geologic indicators to decipher SPR versus SZJ in natural oceanic arc‐continent collisions, such as the distribution of thrust faults, metamorphic rocks, magmatism, crustal thickness, and topography. The numerical simulations help explain the geologic history of Kamchatka in eastern Russia and Banda Arc in eastern Indonesia. This study provides provide new insights and implications diagnosing the polarity of vanished subduction in arc‐continental systems. Key Points: New numerical models with convergent velocity boundary condition for deciphering subduction polarity during arc‐continent collisionsThrust faults, metamorphic rocks, magmatism, topography and Moho morphology can be used as indicators to diagnose subduction polarityThe evolution of subduction polarity reversal well explains the tectonic activities of the Kamchatka and Banda Arc in the Cenozoic [ABSTRACT FROM AUTHOR]

We investigated velocity and anisotropic structure of the crust beneath the eastern margin of the Tibetan Plateau to better understand its deformation and evolution mechanism. We performed H‐κ and Pms anisotropy analyses to obtain crustal thickness, Vp/Vs ratio, fast polarization direction, and splitting time from 711 stations, and further conducted quality control using slowness, harmonic and statistical analyses. The Songpan‐Ganzi Block has a large splitting time and a fast polarization direction roughly parallel to the GPS motion and SKS fast direction. It also shows an overall high but complex distribution of Vp/Vs ratio, and large variations in crustal thickness, indicating that crustal deformation is likely caused by crustal shortening and lower crustal flow. The northern Sichuan‐Yunnan Rhombic Block (SYRB) is featured by a thick crust and high Vp/Vs ratio, suggesting that the crust is likely inflated by partial melting lower crustal rocks. The subblock also exhibits a strong azimuthal anisotropy with a splitting time greater than 0.6 s. The fast polarization direction aligns with the nearly N‐S extended direction and rotates clockwise in front of the Emeishan Large Igneous Province (ELIP). The observed anisotropy agrees with aligned amphibole minerals under a simple shear condition, supporting a southward lower crust flow being diverted by the ELIP. Anisotropy measurements on the southern SYRB are less robust and widely scattered, suggesting a deformation mechanism different from the northern SYRB. In addition, the southeastern margin of the Sichuan Basin shows a systematic pattern of crustal anisotropy consistent with a pure shear deformation mechanism. Plain Language Summary: We studied the crustal structure and deformation beneath the eastern edge of the Tibetan Plateau. By analyzing teleseismic data from 727 stations, we measured crust thickness, Vp/Vs ratio, and azimuthal anisotropy using receiver functions. Our findings show a complex crustal behavior pattern in the eastern Tibet margin. In the Songpan‐Ganzi Block, crustal shortening and lower crust flow seem to be causing deformation. The northern Sichuan‐Yunnan Rhombic Block, with its thick crust and high Vp/Vs ratio, appears to be influenced by partial melting of lower crust rocks. And a southward lower crust flow being diverted by the Emeishan Large Igneous Province. The eastern and southern part of this block shows a different pattern, indicating a unique deformation mechanism. Additionally, the southeastern margin of the Sichuan Basin appears to undergo a distinct type of crustal deformation. Key Points: A new crustal model with much more reliable and denser Pms anisotropic measurements is built in the eastern Tibetan MarginSongpan‐Ganzi Block is likely deformed by crustal shortening and lower crustal flowChannel flow may exist in the west low velocity zone (LVZ) while absent at the east LVZ [ABSTRACT FROM AUTHOR]

Vasculitides are a heterogeneous group of primary disorders which may occur secondary to a variety of conditions. Among them, vasculitis caused by bacterial infection is rare. Here, we present images of CT scans and histology from a 22-year-old young Chinese man with vasculitis secondary to bacterial infection, which is a difficult disease to diagnose. This patient had been diagnosed with antineutrophil-cytoplasmic-antibody-negative vasculitis with pulmonary and renal involvement and was treated with glucocorticoids combined with immunosuppressive agents. However, during his follow up we found that multiple patchy shadows and cavities in both lungs and renal lesions had fluctuated, and the improvement of chest imaging was always related to antibiotic treatment. In addition, renal histology showed capillary loop necrosis and extensive crescent formation, and electron microscopy revealed scattered subepithelial hump-like deposits, which favored the diagnosis of infection over idiopathic vasculitis. Therefore, vasculitis secondary to infection was confirmed. The subsequent therapy response supported our diagnosis. This case is important; since vasculitis secondary to infection is uncommon, our case provides a model for the diagnosis of vasculitis secondary to infection. [ABSTRACT FROM AUTHOR]

In this study, a high‐resolution 3D lithospheric S wave velocity model of the Jiuyishan region is constructed by joint inversion of receiver function and ambient noise. Our Moho depth model reveals relatively thick crust (∼35 km) beneath the Yangtze block and thin crust (∼27 km) beneath the Cathaysia block. The model depicts a complex boundary between these blocks, roughly following the Chenzhou‐Linwu fault in the northern part but gradually curving westward in the southern part between the two blocks. The 3D S wave velocity model shows low‐velocity anomalies in the middle crust, as well as in the upper mantle, interpreted as evidence of asthenospheric upwellings in the upper mantle. These upwellings modify lithosphere structures by changing their temperatures and compositions, and may provide a heat source through the Chenzhou‐Linwu fault for the low‐velocity anomaly in the shallow part beneath Jiuyishan region. Plain Language Summary: The South China block, which is composed of the Yangtze and Cathaysia blocks, has undergone a series of intraplate orogenic episodes since the Neoproterozoic. Location of the southwestern boundary of the Yangtze and Cathaysia blocks has been ambiguous, and the local lithospheric structure is not well constrained. We construct a high‐resolution 3D lithospheric shear velocity model, which provides the first evidence suggesting that the Jiuyishan region is undergoing lithospheric modification. Our model depicts a complex boundary between these blocks, roughly following the Chenzhou‐Linwu fault in northern part but gradually curving westward in the southern part between the two blocks. Moreover, the shear wave velocity structure shows prominent low‐velocity anomalies in the middle crust as well as in the upper mantle. We interpret the low anomalies in mantle as asthenospheric upwellings, which may provide a heat source for the shallow low‐velocity anomaly. Key Points: High‐resolution lithospheric velocity structure as well as Moho depths in the Jiuyishan region are obtained from new seismic array dataBoundary between the Yangtze and Cathaysia blocks roughly follows the Chenzhou‐Linwu fault in the north but curves westward in the southThe asthenospheric upwellings beneath the Jiuyishan region may provide the heat source for a shallow low‐velocity anomaly [ABSTRACT FROM AUTHOR]

DNA methylation has been acknowledged as one of the key epigenetic mechanisms involved in the regulation of gene expression and genomic functions. Alteration of the DNA methylation level has been linked to modification of the disease progression and instability regulation of certain disease-causing repeats in neurodegenerative diseases. In this study, blood samples collected from spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) patients versus control were used to explore the potential link of DNA methylation levels at ATXN3 gene promoter to the pathogenesis of SCA3/MJD. We found that the methylation levels in the ATXN3 promoter were significantly higher in SCA3/MJD patients relative to the controls. Furthermore, higher methylation levels were detected in the SCA3/MJD patients with earlier age at onset and the families with an intergenerational CAG repeats instability. In addition, the first CpG island of the ATXN3 promoter served as the main regulation region of DNA methylation. These findings suggested that an epigenetic change may contribute to the pathogenesis of the SCA3/MJD and provide potential therapeutic targets for CAG repeats–based diseases. [ABSTRACT FROM AUTHOR]