Genotype-phenotype characteristics and baseline natural history of Chinese myelin protein zero gene related neuropathy patients.

BACKGROUND AND PURPOSE: The aim was to characterize the phenotypic and genotypic features of myelin protein zero (MPZ) related neuropathy and provide baseline data for longitudinal natural history studies or drug clinical trials. METHOD: Clinical, neurophysiological and genetic data of 37 neuropathy patients with MPZ mutations were retrospectively collected. RESULTS: Nineteen different MPZ mutations in 23 unrelated neuropathy families were detected, and the frequency of MPZ mutations was 5.84% in total. Mutations c.103_104InsTGGTTTACACCG, c.513dupG, c.521_557del and c.696_699delCAGT had not been reported previously. Hot spot mutation p.Thr124Met was detected in four unrelated families, and seven patients carried de novo mutations. The onset age indicated a bimodal distribution: prominent clustering in the first and fourth decades. The infantile-onset group included 12 families, the childhood-onset group consisted of two families and the adult-onset group included nine families. The Charcot-Marie-Tooth Disease Neuropathy Score ranged from 3 to 25 with a mean value of 15.85 ± 5.88. Mutations that changed the cysteine residue (p.Arg98Cys, p.Cys127Trp, p.Ser140Cys and p.Cys127Arg) in the extracellular region were more likely to cause severe early-onset Charcot-Marie-Tooth disease type 1B (CMT1B) or Dejerine-Sottas syndrome. Nonsense-mediated mRNA decay mutations p.Asp35delInsVVYTD, p.Leu174Argfs*66 and p.Leu172Alafs*63 were related to severe infantile-onset CMT1B or Dejerine-Sottas syndrome; however, mutation p.Val232Valfs*19 was associated with a relatively milder childhood-onset CMT1 phenotype. CONCLUSION: Four novel MPZ mutations are reported that expand the genetic spectrum. De novo mutations accounted for 30.4% and were most related to a severe infantile-onset phenotype. Genetic and clinical data from this cohort will provide the baseline data necessary for clinical trials and natural history studies.

Clinical and genetic features of Charcot-Marie-Tooth disease patients with IGHMBP2 mutations.

Autosomal recessive Charcot-Marie-Tooth disease Type 2S (AR-CMT2S) caused by IGHMBP2 mutation was first reported in 2014, and an increasing number of cases have been reported in the past eight years. We detected 15 distinct IGHMBP2 mutations among 8 typical AR-CMT2S families in our cohort of 178 Chinese CMT2 families using Sanger sequencing and next-generation sequencing (NGS), making IGHMBP2 mutations the most frequent cause of AR-CMT2 in our cohort. From 2014 to 2022, 34 AR-CMT2S families, including 45 patients and 47 different mutations, were reported. One third of identified mutations represented presumed loss-of-function variants (nonsense, frameshift and splicing), while two-thirds were missense changes which clustered in the helicase and ATPase domains. The age at onset ranged from 0.11 years to 20 years (mean±SD: 3.76±3.93 years) and the infantile (0-2 years) onset group accounted for the most patients (51.1%). The initial symptoms included muscle weakness (15, 33.3%), delayed milestones (9, 20%), feet deformity (8, 17.8%), gait disturbance (8, 17.8%), feet drop (7, 15.6%), frequent falls (3, 6.7%), hypotonia (2, 4.4%) and thenar atrophy (1, 2.2%). Molecular structural model analysis of 26 missense IGHMBP2 mutations using PyMOL software revealed that six mutations were close to the RNA-binding channel, eight mutations were in or close to the nucleotide-binding pocket. Based on available limited clinical information, it seems possible that missense changes located in or close to these motifs might be linked to a more severe clinical outcome. In conclusion, IGHMBP2 mutation screening should recommended for early-onset, moderately or severely affected, and sporadic or AR-CMT2 patients. A tiny minority of patients were relatively late onset and mild affected, which should be given more attention in genetic diagnosis and treatment. While our preliminary analysis suggests a potential link between the localization of missense mutations and clinical presentation, definition of genotype-phenotype relationships will require harmonized clinical information from a larger series of patients.

Establishment and practice of the collaborative innovation system of the national clinical research center for geriatric disorders / 中华医院管理杂志

Scientific and efficient collaborative innovation system plays a key role in driving the construction and development of national clinical medical research centers. As the entity in building the national clinical medical research center for geriatric diseases, Xiangya Hospital of Central South University has carried out the " two-in-one integration" construction of the center hospital based on the principle of " simultaneous construction of the center and the hospital" . Leveraging the research, promotion and application of key technologies for common diseases and frequently occurring diseases among the elderly, a collaborative innovation system has come into being since 2018, consisting of three organically linked platforms of technology support platform, core research platform and public service platform, as well as four support systems of collaborative innovation network support system, innovation management system support system, special innovation fund support system and innovation ability training support system. By 2021, the collaborative innovation system has been completed in general, and desirable results have been achieved in clinical research, achievements translation and technology promotion for geriatric diseases. These achievements have strongly promoted the development of China′s elderly health sector.

Research advances in clinical scales for essential tremor / 中华老年医学杂志

Essential tremor(ET)is one of the most common movement disorders, with a prevalence of 4.6% in people over 65 years old.Action tremor of both upper limbs at 4-12 Hz action tremor in both upper limbs is the main clinical feature of ET patients.ET was previously considered to be a benign isolated symptomatic disease, but in recent years, researches have found that ET is a family of diseases with high clinical and genetic heterogeneities.In addition to tremor, it can also be accompanied by soft neurological signs and various non-motor symptoms, leading to different degrees of function impairment in patients.Early comprehensive evaluation and long-term follow-up of patients with ET are essential.The standardized scale is the most important tool for ET assessment.This article reviews various tremor assessment scales.

Research progress on the association between Parkinson′s disease and inflammatory bowel disease in genetics and gut microbiota / 中华神经科杂志

Parkinson′s disease (PD) is a common degenerative disease of central nervous system. PD is closely related to gastrointestinal diseases in comorbidity studies, and the “gut brain axis” disorder may be involved in their relationship. In recent years, relevant studies have suggested that there are genetic and epidemiological evidences to link PD with inflammatory bowel disease (IBD). This article reviews the relationship between PD and IBD from the genetic evidence and the relevant concept of “gut brain axis”.

Advances in the TAF1 gene / 中华神经科杂志

TAF1 gene encodes TATA-box binding protein-associated factor-1, which serves as a scaffold for the assembly of the transcription factor ⅡD and participates in the transcription of many genes in eukaryotic cells. Human TAF1 possesses intrinsic protein kinase activity, histone acetyltransferase activity as well as ubiquitin-activating and conjugating activity, and these activities have been mapped to different domains. Currently, TAF1 has been identified as the causative gene of X-linked dystonia-parkinsonism and X-linked mental retardation. What′s more, a series of functional analysis have demonstrated the importance of TAF1 gene in cell cycle and cell growth, and its relationship with neurodevelopment and tumorigenesis has also been reported. This review summarizes the research progress of TAF1 including structure, phenotypes and biological function.

Recent advance in Parkinson's disease with excessive daytime sleepiness / 中华神经医学杂志

Excessive daytime sleepiness (EDS) is a common sleep disturbance in Parkinson's disease (PD), and the prevalence of EDS in PD patients is obviously higher than that in the normal population. EDS not only seriously influences the quality of life of PD patients but also increases the risk of accidents while driving and the risk of falling, therefore, timely recognition and intervention of EDS are of great importance. In order to deepen the understanding of EDS, this review will summarize the recent advance in epidemiology, etiology and pathogenesis, clinical significance, neuroimaging, clinical assessment, and clinical management of EDS.

Research progress of somatosensory involvement in amyotrophic lateral sclerosis / 中华神经科杂志

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the degeneration of upper and lower motor neurons selectively. Although the motor system lesion is the most predominant clinical manifestation of ALS, with the progression of the understanding of the pathogenesis and clinical detection of the disease, more and more patients are found to have extra-motor features of ALS, such as somatosensory involvement, etc. The research results demonstrated that ALS might be a kind of disorder combined with sensory disturbance according to the electrophysiology, neuropathology, neuroimaging, animal model simulation, genetic evidence, and other methods detected. We, herein, review the prevalence and detection methods especially the aspect of genetic associations implicated in the sensory nerve disturbance of ALS.

Research advances in the treatment of essential tremor / 中华神经科杂志

Essential tremor (ET) is a common movement disorder. It is characterized by a distinctive 4-12 Hz action tremor typically affecting bilateral upper limbs. Existing drugs for ET mainly include β-blockers, anticonvulsants, benzodiazepines, etc. However, the efficacy of existing drugs is limited. With the development of the medical research, some progress has been made in the treatment of ET. The review will explore the recent advances in the treatment of ET,such as new drugs, surgical treatment, repetitive transcranial magnetic stimulation, rehabilitation treatment, etc., in order to provide clinical application prospects.

Effect of CAG repeats on the age at onset of patients with spinocerebellar ataxia type 2 in China / 中南大学学报(医学版)

Objective: Spinocerebellar ataxia type 2 (SCA2) is one of the most common autosomal dominant ataxias in the world. Several reports revealed that CAG repeats in some polyQ-containing genes may affect the age at onset (AAO) of patients with SCA2, however, little studies were conducted among Chinese patients with SCA2. Thus, the aim of this study is to evaluate the effect of CAG repeats on the AAO of patients with SCA2 in China.Methods:A total of 119 patients with SCA2 were enrolled and were divided into 2 groups according to their major phenotype:17 patients from 9 families with Parkinson ' s syndrome were grouped as the Parkinson ' s disease-SCA2 (PD-SAC2); 91 patients from 66 SCA2 families and 11 sporadic SCA2 patients were grouped as the ataxia-SCA2 (A-SCA2). Blood samples were obtained from the subjects, and the CAG repeat length in ATXN2 and other (CAG)n-containing genes was screened using fluorescent PCR. The Spearman ' s rank correlation between the CAG repeat length in (CAG)n-containing genes and AAO was analyzed. Regression analysis was performed to investigate whether the CAG repeat length could explain the variant of AAO. A t-test was used to compare the difference of CAG repeat length in (CAG)n-containing genes between the PD-SAC2 and A-SCA2 groups. Results:The CAG repeat length in the longer allele of ATXN2 was negatively correlated with AAO of SCA2 (R=?0.251, P<0.05), and the CAG repeat length could explain 41.7％of the variation of AAO. AAO negatively correlated with the CAG repeat length in the shorter allele of ATXN7 (R=?0.251, P=0.006) or in the longer allele of TBP gene (R=?0.197, P=0.034). A tendency of delay in the AAO was also observed in patients with SCA2 carrying the CAG repeat within the ATXN3, CACNA1A, ATXN7, TBP, and RAI1. In addition, we found that the CAG repeat length in ATXN7 and ATXN2 between the A-SCA2 and the PD-SCA2 groups was significantly different (both P<0.05).Conclusion:The CAG repeat in ATXN2 is a major genetic factor for the AAO of patients with SCA2 in China. The CAG repeat length in ATXN3, CACNA1A, ATXN7, TBP, and RAI1 genes might be a potential factor associated with the AAO of SCA2. The CAG repeat in ATXN7 might be a potential factor affecting the Parkinson??s syndrome in SCA2.

The phenotypic and genetic spectrum of colony-stimulating factor 1 receptor gene-related leukoencephalopathy in China / 中华神经科杂志

Objective:To summarize and analyze the clinical data of Chinese patients with colony-stimulating factor 1 receptor (CSF1R)-related leukoencephalopathy, and clarify the phenotypic and genetic characteristics of Chinese patients.Methods:Medical history of patients with CSF1R-related leukoencephalopathy diagnosed from April 1, 2018 to January 31, 2021 in the department of neurology of 22 hospitals in China was collected, and scores of Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment Scale (MoCA), magnetic resonance severity scale were evaluated. Group comparison was performed between male and female patients.Results:A total of 62 patients were included, and the male-female ratio was 1∶1.95. The age of onset was (40.35±8.42) years. Cognitive impairment (82.3%, 51/62) and motor symptoms (77.4%,48/62) were the most common symptoms. The MMSE and MoCA scores were 18.79±7.16 and 13.96±7.23, respectively, and the scores of two scales in male patients (22.06±5.31 and 18.08±5.60) were significantly higher than those in females (15.53±7.41 , t=2.954, P=0.006; 10.15±6.26, t=3.328 , P=0.003). The most common radiographic feature was bilateral asymmetric white matter changes (100.0%), and the magnetic resonance imaging severity scale score was 27.42±11.40, while the white matter lesion score of females (22.94±8.39) was significantly higher than that of males (17.62±8.74 , t=-2.221, P<0.05). A total of 36 CSF1R gene mutations were found in this study, among which c.2381T>C/p.I794T was the hotspot mutation that carried by 17.9% (10/56) of the probands. Conclusions:The core phenotypic characteristics of CSF1R-related leukoencephalopathy in China are progressive motor and cognitive impairment, with bilateral asymmetrical white matter changes. In addition, there exist gender differences clinically, with severer cognitive impairment and imaging changes in female patients. Thirty-six CSF1R gene mutations were found in this study, and c.2381T>C/p. I794T was the hotspot mutation.

Pay attention to repeat expansion mutation related neurogenetic diseases / 中华神经科杂志

Repeat expansion diseases (REDs), which include Huntington disease, spinocerebellar ataxia and fragile X syndrome, are important part of the neurogenetic diseases. REDs are caused by expansions of sequence repeats in the human genome. The REDs spectrum expanded rapidly with the advances of technology regarding molecular genetics in recent years. Although rare, these genetic disorders can be frequently met by neurologists. This article introduces the definition, classification, diagnosis and new progresses in treatment of REDs based on the most recent research findings.

Mechanism of re-emergent tremor in Parkinson′s disease / 中华神经科杂志

Parkinson′s disease is a common degenerative disease of the central nerve system, mainly caused by the degeneration of dopaminergic neurons in the compact part of substantia nigra. Tremor is one of the most common symptoms of Parkinson′s disease. Part of patients changing posture position could cause the tremor suspended for a period of time, after that, the tremor appear again. This clinical phenomenon is characterized by the reproducibility of Parkinson′s disease tremor, called re-emergent tremor (RET). The cause of RET mechanism is still unclear and the relative researches are less. This review summarizes the possible mechanism, clinical features and significance of RET in Parkinson′s disease.

Advances in research on myoclonus-dystonia syndrome / 中华神经科杂志

Myoclonus-dystonia syndrome (MDS) is a special type of dystonia-plus syndromes. It is an autosomal-dominant movement disorder syndrome characterized by myoclonus and dystonia and accompanied by certain mental symptoms. The disorder usually occurs in childhood. Myoclonus and dystonia are usually involved in upper limbs, trunk and neck. The main pathogenic gene of MDS is ε-sarcoglycan gene (SGCE). Up to date, the mechanism that how this gene leads to the disease is not clear. The continuous progress of MDS can cause disability and bring great pain to patients and their families. In recent years, significant progress has been made in the research of this disease. This article will systematically review the pathogenesis, clinical phenotype, genetics, diagnostic criteria, differential diagnosis and treatment of MDS.

Clinical, pathologic and genetic analysis of 3 families with dystrophinopathy / 中华实用儿科临床杂志

Objective:To explore the phenotypic and genotypic characteristics of 3 Chinese families with dystrophinopathy, so as to provide the data for earlier diagnosis and therapy.Methods:The clinical, muscle pathology and electrophysiological data from the 3 families with dystrophinopathy were analyzed.The perpheral venous blood of 15 members from the 3 families was collected.Meanwhile, the known genes that were related to neuromyopathy were detected.Results:There were 8 patients in the 3 families.All the patients presented progressive weakness of extremities as the main manifestation, with elevated creatine kinase (CK) and myogenic changes in electrophysiological examination.The proband of family 1 was a 15 years old boy with 1 year history.He displayed limb weakness and accompanied with muscle pain after exercise.Muscle pathology only revealed denatured and atrophy muscle fibers, without necrosis and hyperplastic muscle fibers.The proband of family 2 was a 9 years old boy with 1 year history.His muscle pathology illustrated degeneration, necrosis, proliferation and lipid deposition muscle fibers.The proband of family 3 was a 16 years old boy with 10 years history.He exhibited generalized muscle atrophy, spine and chest deformity.His muscle pathology demonstrated classical muscular dystrophy changes.Gene detection gave information that deletion mutation in exons 45 to 47 of DMD gene in family 1 proband.c.2636 T> G mutation in exons 18 of DMD gene in family 2 proband, repeat mutation in exons 61 to 76 of DMD gene in family 3 proband; c.2636T>G was classified as pathogenic variation according to the guidelines for the interpretation of sequence variants of the American college of medical genetics and genomics guidelines. Conclusions:The phenotype of dystrophinopathy is related to genotype.A new mutation of DMD gene c. 2636T>G is discovered.Early patient with dystrophinopathy can only display pained weakness of muscle after exercise.Muscle pathology and gene detection should be performed as soon as possible.

Expert consensus on the management strategy of patients with hereditary ataxia during prevention and control of novel coronavirus pneumonia epidemic / 中华医学遗传学杂志

Since December 2019, a series of highly infectious cases of unexplained pneumonia have been discovered in Wuhan, Hubei Province, which have been confirmed as '2019 corona virus disease' caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 virus can invade many human systems including the lungs. Patients with central nervous system involvement may show a series of neurological symptoms, which is easy to be misdiagnosed and neglected, thereby increasing the risk of SARS-CoV-2 transmission. Hereditary ataxia is a large group of neurodegenerative diseases with great clinical and genetic heterogeneity and high mortality and disability. In view of the seriousness of the COVID-19 epidemic, a series of prevention and control measures adopted by the government have restricted the follow-up, diagnosis and treatment of patients by the hospitals, which has a great impact on their mental and physical health. In order to standardize the management of patients during the prevention and control of COVID-19 epidemic, the Specialized Committee of Neurogenetics of the Neurophysician Branch of Chinese Medical Doctor Association has formulated this consensus, with an aim to help patients to overcome the difficulties and pass the epidemic prevention period safely.

Clinical, imaging and genetic analyses of two Chinese families with oculopharyngeal muscular dystrophy / 中华神经医学杂志

Objective:To study the clinical, imaging and genetic characteristics of two Chinese families with oculopharyngeal muscular dystrophy (OPMD).Methods:The clinical data of the two families found in our hospital in August 2016 and May 2018 were analyzed. All the members were investigated in detail, and the clinical and imaging data of the probands were analyzed. Blood samples were collected from 22 members of the two families and PABPN1 gene analysis was performed. Results:There were 4 patients in family 1 with four generations and 4 patients in family 2 with three generations. The two probands presented ptosis, dysphagia at the age of 50 and 55. The proband of family 1 also showed diplopia, amyotrophy, weakness of proximal limbs, neurogenic changes in electromyogram (EMG), muscle fibers with rimmed vacuoles in muscle pathology, aspiration pneumonia in chest CT, and brainstem symmetric white matter lesions in cranial MR imaging. The proband of family 2 also showed eye muscle paralysis and lateral limb weakness, myogenic changes in EMG, bilateral parietal and right frontal lacunar infarctions in cranial MR imaging. Analysis of PABPN1 gene showed that the repeated mutation of PABPN1 trinucleotide (GCN) in 2 families was amplified from normal (GCG) 6(GCA) 3(GCG) to (GCG) 6(GCA) 3(GCG) 2(GCA) 3(GCG). Conclusion:OPMD has clinical heterogenicity; symmetrical white matter lesions in the brainstem might be found in cranial MR imaging; Chinese patients with OPMD have PABPN1 gene mutation, specificly manifested as (GCG) 6(GCA) 3(GCG) 2(GCA) 3(GCG) repeat mutations.

Genetic and clinical features of sorbitol dehydrogenase gene-related Charcot-Marie-Tooth disease in Chinese population / 中华神经科杂志

Objective:To report the genetic and clinical features of sorbitol dehydrogenase (SORD) gene-related Charcot-Marie-Tooth disease (CMT) in Chinese population.Methods:Fifty-seven undiagnosed sporadic or autosomal recessive (AR) inherited CMT2 families were collected from the Department of Neurology of the Third Xiangya Hospital from 2009 through 2018 .Polymerase chain reaction combined with Sanger sequencing were used to detect the mutations of SORD gene, and the relative clinical features were summarized. Results:The homozygous SORD gene hot spot mutation c.757delG (p. Ala253GlnfsTer27) was detected in four sporadic patients, accounting for about 7% of the total. Two patients with CMT2 phenotype were characterized by progressive lower limb weakness and atrophy with electromyogram changes of axonal degeneration in both motor and sensory nerves. Two patients with distal hereditary motor neuropathy (dHMN) phenotype exhibited progressive lower limb weakness and atrophy with electromyogram changes of axonal degeneration in motor nerves only. The age of onset was between five and 16 years, and the CMT neuropathy score was 2-9.Conclusions:The homozygous hot spot mutation of SORD gene (c.757delG, p.Ala253GlnfsTer27), and related childhood or adolescence onset, mildly affected CMT2/dHMN phenotypes are firstly reported in Chinese population. SORD gene-related CMT might be the most common subtype of AR-CMT2.

Recent advance in CAPOS syndrome / 中华神经医学杂志

CAPOS syndrome,manifested as cerebellar ataxia,areflexia,pes cavus,optic atrophy,and sensorineural deafiness,is one of the ATP1A3 gene-related disorders with an autosomal dominant inheritance pattern.The specific pathogenesis of the disease is currently unclear and the clinical manifestations are complicated.This review will provide an overview of CAPOS syndrome in the aspect of pathogenesis,clinical manifestations,diagnosis,differential diagnosis and treatment.

A review on evaluating application of abnormal iron deposition in brain on diagnosis and differential diagnosis of Parkinson's disease / 中华老年医学杂志

Parkinson's disease (PD)is a common neurological degenerative diseases,and its diagnosis mainly depends on a patient's clinical manifestations and the response to dopaminergic drugs.The coincidence rate between clinical diagnosis and pathological diagnosis for PD is only 70％-80％.It is found that abnormality of intracranial iron deposition is one of the important pathological changes in PD progression.Therefore,it can be helpful to detect the abnormal iron deposition in brain using MRI and Doppler sonography for early diagnosis and differential diagnosis of PD.