OBJECTIVE: To explore the genetic variants and phenotypic characteristics of patients with Neurofibromatosis type I (NF1). METHODS: Twenty two NF1 patients who presented at Enze Medical (Center) Group in Taizhou between 2018 and 2024 were selected as the study subjects. Clinical phenotype and family history were collected for the patients. Whole exome sequencing (WES) was carried out for the 22 probands to screen the variants of NF1 gene. Candidate variants were verified by Sanger sequencing of their family members. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: K20230902). RESULTS: The 22 probands were diagnosed between the age of 5 months to 47 years old, and have all shown cafe au lait spots on their skin. Seventeen patients exhibited the phenotype at birth, and 11 had various degrees of neurofibromatosis. Among them, probands 1 and 13 underwent surgical resection of the tumor but had recurred, while proband 12 had amputation due to the huge size and serious impact of the neurofibroma and had no recurrence. Five patients had various degrees of scoliosis. In total 22 germline mutations and one somatic mutation were identified among the 22 families, with 5 variants unreported previously, including 1 nonsense mutation c.1603C>T (Q535*), 3 frameshift mutations [c.7268_7269delCA (Thr2423fs), c.2293del (Arg765Alafs*26), and c.5433_5438delinsGC (Phe1812ArgfsTer50)], and 1 deletion involving exons 41-44 of the NF1 gene and adjacent introns. Proband 13 was found to harbor germline mutation c.6796C>T (Gln2266Ter) and somatic mutation c.1019_1020del (Ser340Cysfs Ter12) in the peripheral blood and tumor tissue, respectively. Among the 22 NF1 probands, 6 had received treatment due to severe illness. Proband 1 had tumor resection in the right upper limb, but was found to have malignant lung tumor and died during follow-up. Proband 12 had multiple recurrence of neurofibroma in the left ring finger. Proband 4 underwent spinal correction surgery due to severe scoliosis. Proband 11 had died due to a central nervous system disease. Among the 22 germline mutations, 6 had led to the occurrence of truncated proteins, which may have a more severe impact on the phenotype. CONCLUSION This study investigated the genetic variants and clinical phenotypes of 22 NF1 families and identified 5 novel variants of the NF1 gene, which has expanded the genotypic and phenotypic spectra of the NF1. Preliminary studies have identified an association between truncated mutations, young age, and severe phenotypes, which may provide important clues for prognosis evaluation. For the clinical diagnosis and treatment of NF1, it is necessary to consider the phenotypic characteristics and genetic testing in combination with genetic counseling and long-term follow-up.
Humans ; Neurofibromatosis 1/pathology* ; Male ; Female ; Pedigree ; Adult ; Child ; Child, Preschool ; Middle Aged ; Adolescent ; Infant ; Young Adult ; Neurofibromin 1/genetics* ; Phenotype ; Asian People/genetics* ; Mutation ; Exome Sequencing ; East Asian People

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with Hereditary spastic paraplegia type 3A (SPG3A) and the genotype-phenotype correlation. METHODS: A three-generation pedigree presented at Huantai Maternal and Child Health Care Hospital in March 2021 was selected as the study subject. Whole-exome sequencing (WES) and pedigree analysis was carried out. Candidate variant was validated by Sanger sequencing of the members from the pedigree. Haplotype analysis was used to trace the origin of the variant, and pathogenicity was rated based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: 2025-12). RESULTS: A c.1024C>T (p.Pro342Ser) variant of the ATL1 was identified in the four affected members, including the proband, but none of the three unaffected relatives. Haplotype analysis suggested that the variant was derived from the proband's mother and has co-segregated with the disease phenotype. Based on the guidelines of the ACMG, it was classified as likely pathogenic. CONCLUSION The ATL1 c.1024C>T (p.Pro342Ser) variant probably underlay the pathogenesis in this pedigree. Above finding has enriched the mutational spectrum of ATL1 and phenotypic spectrum of SPG3A in the Chinese population, and enabled genetic counseling for this pedigree.
Humans ; Pedigree ; Spastic Paraplegia, Hereditary/genetics* ; Male ; Female ; Asian People/genetics* ; Adult ; Haplotypes ; Membrane Proteins/genetics* ; Exome Sequencing ; GTP-Binding Proteins/genetics* ; Mutation ; Middle Aged ; China ; Genetic Association Studies ; East Asian People

INTRODUCTION

Neurofibromatosis type 1 (NF1) is an autosomal dominantly inherited condition seen in one of 4000 live births, predisposing to peripheral and central neurofibromas. Spinal tumors are seen in 40% of cases with NF1 and only 2% will develop symptoms, and among those who develop symptoms where 33% showed intradural extramedullary location. Thoracic spinal dumbbell neurofibroma is even rarer, and cases that extend to obliterate the posterior mediastinum even more so, with the case presented being the largest in size documented to date.

A 34-year-old female presented since childhood clinical findings consistent with Neurofibromatosis Type I: generalized cafe-au-lait macules, axillary freckling, cutaneous neurofibromas, two iris Lisch nodules identified via slit lamp examination, and anterolateral bowing of the right tibia, and no known parental history of Neurofibromatosis Type I. Prior to admission, the patient presented with progressive loss of motor strength of the lower extremities, and progressive dyspnea. Work-up revealed a Thoracic Intradural Extramedullary Neurofibroma extending to the Right Posterior Mediastinum measuring 15.3 cm x 12.9 cm x 9.7 cm in the thoracic cavity compressing the right lung and bronchus. An extensive two stage surgery was contemplated involving an initial resection of the Intradural mass, with spine instrumentation for support, and subsequent resection of the mediastinal extension. However, complications from the compressing tumor: complete cord transection syndrome causing spinal autonomic dysfunction, lung and airway compromise causing prolonged intubation and difficulty in weaning from mechanical ventilatory support, extensive thrombus formation in the right jugular vein, and nosocomial infections all created compounding difficulties for the surgical technique and anesthetic plan.

Cornerstone management for dumbbell spinal neurofibromas involves their total removal. The best results are obtained in patients showing minimal neurological deficits during the preoperative period. However, little improvement may be expected from patients who develop complete transection syndrome during the postoperative period. Concurrent medical management to prepare the patients are equally important. The multi-subspecialty approach required in managing these cases entails a good balance between the disability before the surgery, anticipated outcomes, and quality of life of the patients.

OBJECTIVE: To investigate the short-to-medium-term clinical efficacy of total hip arthroplasty(THA) with Pinnacle ES constrained liner in the treatment of femoral neck fractures(FNF) associated with lower limb neuromuscular disorders. METHODS: A retrospective analysis was conducted on 16 patients who underwent primary THA using Pinnacle ES constrained liner for FNF with lower limb neuromuscular disorders and had complete follow-up data, treated between January 2020 and January 2023. There were 7 males and 9 females, with a mean age of (68.42±3.58) years old ranging from 61 to 75 years old. Among them, 10 cases had left-sided fractures and 6 had right-sided fractures;based on the Garden classification, 11 cases were type Ⅲ and 5 cases were type Ⅳ. The affected limbs were complicated with sequelae of poliomyelitis (2 cases), Parkinson's disease (2 cases), and sequelae of cerebral infarction (12 cases). All operations were performed via a posterolateral approach. Prosthesis position was evaluated using imaging data. Hip function was assessed by the Harris hip score(HHS) and Merle D'Aubigne hip score. During the follow-up period, the occurrence of complications such as prosthetic dislocation, loosening, and infection was recorded. RESULTS: One patient died of advanced tumor 2 years after surgery, and the remaining 15 patients were followed up for 24 to 64 months with a mean of (34.8±5.5) months. The operation time ranged from 50 to 90 minutes with a mean of (75.56±8.15) minutes, and the blood loss ranged from 150 to 200 ml with a mean of (170.32±12.56) ml. All patients achieved primary wound healing after surgery. Intraoperatively, femoral calcar splitting occurred in 2 cases, which were treated with titanium cable binding;no neurovascular injuries were observed in any case. The mean HHS increased from (18.95±2.25) preoperatively to (88.02±2.42) at the last follow-up, and the mean Merle D'Aubigne Score increased from (3.05±0.06) preoperatively to (16.65±0.93) at the last follow-up. Postoperative follow-up X-rays showed good prosthetic position, and no complications such as dislocation, prosthetic loosening, periprosthetic fracture, or deep infection occurred during the follow-up period. CONCLUSION Total hip arthroplasty with Pinnacle ES constrained liner is effective in the treatment of femoral neck fractures associated with lower limb neuromuscular disorders. It can significantly improve hip function, reduce the postoperative prosthetic dislocation rate, provide good initial stability, and achieve satisfactory short-to-medium-term clinical efficacy.
Humans ; Male ; Female ; Middle Aged ; Aged ; Arthroplasty, Replacement, Hip/methods* ; Femoral Neck Fractures/complications* ; Retrospective Studies ; Neuromuscular Diseases/surgery* ; Lower Extremity ; Treatment Outcome

Spinal muscular atrophy (SMA) is a common fatal autosomal recessive genetic disorder in childhood, primarily caused by homozygous deletion of the SMN1 gene. Its main characteristics include the degenerative changes in the anterior horn motor neurons of the spinal cord, leading to symmetrical progressive muscle weakness and atrophy of the proximal limbs. However, SMA patients with the same genetic background often exhibit different degrees of disease severity. In addition to the well-established modifier gene SMN2, the effect of other modifier genes on clinical phenotypes should not be overlooked. This paper reviews the latest advancements in the pathogenic and modifier genes of SMA, aiming to provide a deeper understanding of the pathogenic mechanisms and phenotypic differences in SMA, as well as to offer new strategies and targets for treating this condition.
Humans ; Muscular Atrophy, Spinal/genetics* ; Phenotype ; Survival of Motor Neuron 1 Protein/genetics* ; Genes, Modifier ; Survival of Motor Neuron 2 Protein/genetics*

OBJECTIVES: To explore the efficacy and adverse reactions of nusinersen combined with risdiplam in the treatment of spinal muscular atrophy (SMA). METHODS: A retrospective analysis was conducted on the clinical data of 10 pediatric SMA patients treated with nusinersen combined with risdiplam at the Children's Medical Center of Xiangya Hospital, Central South University. RESULTS: Among the 10 SMA patients, there were 4 with type I, 4 with type II, and 2 with type III. Nine patients initially received nusinersen monotherapy, while 1 patient received nusinersen combined with risdiplam. The median duration of combination therapy with nusinersen and risdiplam for the 10 patients was 10.5 months (range: 0.5-20.0 months), with 6 patients undergoing combination therapy for more than 6 months, showing improvements in motor and/or respiratory function. The remaining 4 patients had combination treatment durations of 0.5, 1.0, 1.3, and 4.0 months, respectively, with no significant overall improvement. After combined treatment, 5 patients experienced skin hyperpigmentation, 2 had lumbar puncture site pain, 1 experienced vomiting, 1 had increased sputum production, and 1 had reduced total sleep time. All adverse reactions were mild and did not require medical intervention. CONCLUSIONS Nusinersen combined with risdiplam demonstrates efficacy in the treatment of SMA, and no significant adverse reactions have been observed.
Humans ; Oligonucleotides/adverse effects* ; Male ; Female ; Child, Preschool ; Retrospective Studies ; Infant ; Muscular Atrophy, Spinal/drug therapy* ; Drug Therapy, Combination ; Child ; Azo Compounds ; Pyrimidines

Duchenne muscular dystrophy (DMD) is an X-linked recessive neuromuscular disorder characterized primarily by progressive degeneration and necrosis of skeletal muscle, resulting from mutations in the Dystrophin gene. Patients with DMD typically present with progressive muscle weakness and atrophy during childhood. Currently, available treatment options for DMD remain limited and their efficacy is suboptimal. This review aims to provide a systematic overview of recent advances in therapeutic strategies for DMD, including an analysis of the mechanisms underlying various treatment approaches, outcomes from clinical trials, and their potential clinical applications, in order to inform and guide clinical decision-making.
Muscular Dystrophy, Duchenne/genetics* ; Humans ; Genetic Therapy

OBJECTIVES: Uridine diphospho-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) myopathy is a progressive neurodegenerative disease associated with homozygous or compound heterozygous missense mutations in the GNE gene. This study aims to explore the impact of the homozygous p.V543M mutation in on cell phenotype and to gain preliminary insights into the underlying mechanisms. METHODS: Human embryonic kidney 293T (HEK 293T) cells were used to construct wild-type (WT-GNE) and mutant (MUT-GNE) GNE overexpression models. Western blotting and immunofluorescence were used to assess GNE protein expression levels and subcellular localization. Cell adhesion, proliferation, apoptosis, and mitochondrial membrane potential were evaluated using the cell counting kit-8 (CCK-8) assay, crystal violet staining, flow cytometry, Hoechst 33342/propidium iodide (PI) staining, and tetramethylrhodamine ethyl ester (TMRE) staining. Sialic acid synthesis levels and GNE enzymatic activity were measured, and the mRNA expression of sialic acid biosynthesis-related enzymes was quantified by real-time PCR. RESULTS: Western blotting confirmed successful establishment of GNE overexpression models. Immunofluorescence showed significantly reduced co-localization of GNE protein with Golgin-97 in the MUT-GNE group compared to WT-GNE (Pearson's correlation coefficient: 0.65±0.08 vs 0.83±0.06, P<0.05). Compared with WT-GNE, cells in the MUT-GNE group exhibited increased adhesion, decreased proliferation, and reduced mitochondrial membrane potential (P<0.05). No significant differences in apoptosis were observed between groups. The MUT-GNE group showed reduced sialic acid production, significantly decreased kinase activity, and downregulated transcription of sialic acid biosynthesis-related enzymes compared to WT-GNE (P<0.001). CONCLUSIONS The p.V543M mutation in the GNE gene alters cellular phenotype by reducing GNE enzymatic activity and the transcription of sialic acid biosynthesis enzymes, ultimately impairing sialic acid production.
Humans ; Mutation, Missense ; HEK293 Cells ; Apoptosis/genetics* ; Phenotype ; Multienzyme Complexes/metabolism* ; Cell Proliferation ; Homozygote ; Cell Adhesion/genetics* ; Distal Myopathies/genetics*

Neurofibromatosis Type 1 （NF1） is an autosomal dominant hereditary neurological disorder. One of the typical manifestations of NF1 is neurofibroma, which can develop gradually over time. When the volume exceeds 100 cm², it is referred to as giant neurofibroma, representing a tumor-like proliferation of Schwann cells within the nerve fiber sheath. The Department of Otolaryngology at the Affiliated Hospital of Guangdong Medical University received a rare case involving a patient with giant neurofibromatosis affecting the maxillofacial region, neck, and chest. The patient underwent successful surgical treatment with the collaboration of various medical disciplines.
Humans ; Head and Neck Neoplasms/surgery* ; Neck ; Neurofibromatoses ; Neurofibromatosis 1/surgery* ; Thoracic Neoplasms/surgery*

Duchenne muscular dystrophy (DMD) is an X-linked recessive myopathy caused by mutations in the dystrophin gene, which is divided into presymptomatic, early ambulatory, late ambulatory, early non-ambulatory, and late non-ambulatory stages according to its disease progression. Some patients experience non-progressive cognitive developmental delays in the presymptomatic stage. DMD patients gradually develop osteoporosis, cardiomyopathy, decreased respiratory function, delayed puberty, and gastrointestinal symptoms as the disease progresses. The required multidisciplinary management strategies vary across different disease stages. To standardize the multidisciplinary management of DMD, we established the DMD Guideline Writing Committee under the authorization of Chinese Medical Association Rare Disease Branch. Combined with the questions raised by patients in multiple consultations, neuromuscular experts drafted the DMD guidelines based on published clinical evidence, current practices, and expert recommendations. A consensus was reached on the best-practice recommendations for DMD management after extensive consultations with specialists from multiple relevant disciplines. The resulting recommendations have been endorsed by Chinese Medical Association Rare Disease Branch. This guideline provides practical and reasonable recommendations for all healthcare professionals and caregivers involved in DMD management, ensuring that patients can receive high-standard medical treatment and care across our country, which also serves as a reference for government staff involved in DMD management.
Humans ; Muscular Dystrophy, Duchenne/therapy* ; China