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

Membrane-bound organelles and membraneless organelles (MLOs) coordinate various biological processes within eukaryotic cells. Among these, stress granules (SGs) are significant cytoplasmic MLOs that form in response to cellular stress, exhibiting liquid-like properties alongside stable substructures. SGs interact with diverse organelles, thereby influencing cellular pathways that are critical in both health and disease contexts. This review discusses the interplay between SGs and organelles and explores the methodologies employed to analyze interactions between SGs and other MLOs. Furthermore, it highlights the pivotal roles SGs play in regulating cellular responses and the pathogenesis of amyotrophic lateral sclerosis. Gaining insights into these interactions is essential for deciphering the mechanisms underlying both physiological processes and pathological conditions.
Humans ; Stress Granules/pathology* ; Organelles/metabolism* ; Amyotrophic Lateral Sclerosis/pathology* ; Animals ; Stress, Physiological ; Cytoplasmic Granules/metabolism*

OBJECTIVE: To assess the carrier frequency of spinal muscular atrophy (SMA) in women of childbearing age in Chongqing and to evaluate prenatal diagnostic outcomes in high-risk couples. METHODS: A total of 17 926 women of childbearing age attending Chongqing Health Center for Women and Children between May 2021 and November 2023 were enrolled, including 3 398 pre-pregnant women and 14 528 pregnant women, all of whom had no clinical phenotype or family history of SMA or related neuromuscular disorders. Real-time quantitative PCR (RT-qPCR) was used to determine the copy number variations in exons 7 and 8 (E7, E8) of the SMN1 gene. High-risk carriers were identified based on the genetic screening results. Multiplex ligation-dependent probe amplification (MLPA) was employed for prenatal diagnosis of fetuses from high-risk couples. This study was approved by the Medical Ethics Committee of Chongqing Health Center for Women and Children (Ethics No.2021-RGI-02). RESULTS: Among the 17 926 women of childbearing age, 298 (1.66%) were identified as heterozygous carriers, including 278 (1.55%) with concurrent deletions of E7 and E8, and 20 (0.11%) with isolated deletions of E7. Seven high-risk couples were identified, six of whom were prenatal couples. Of the two fetuses from these high-risk pregnancies, both exhibited heterozygous deletions of E7 and E8 in the SMN1 gene, while four fetuses showed no abnormalities. CONCLUSION This study provides a comprehensive assessment of the carrier frequency of SMA among women of childbearing age in Chongqing, offering valuable data for the primary and secondary prevention of SMA-related birth defects in the region.
Humans ; Female ; Muscular Atrophy, Spinal/diagnosis* ; Pregnancy ; Prenatal Diagnosis/methods* ; Adult ; Survival of Motor Neuron 1 Protein/genetics* ; Genetic Carrier Screening/methods* ; DNA Copy Number Variations/genetics* ; China ; Genetic Testing ; Heterozygote

OBJECTIVE: To explore the clinical features and genetic basis of a male patient with Kennedy disease(KD) presenting as secondary infertility. METHODS: A male patient who had presented at Yantai Yuhuangding Hospital in August 2023 for secondary infertility for 5 years was selected as the study subject. Clinical data, laboratory findings, and auxiliary examination of the patient were collected. Peripheral blood samples were obtained from the patient and his family members. Following DNA extraction, whole-exome sequencing (WES) was carried out. Pathogenicity of candidate variant was predicted by bioinformatics analysis. Fluorescence probe PCR-capillary electrophoresis was employed to analyze the trinucleotide CAG repeat sequence variation in the AR gene to rule out dynamic mutation. This study was approved by the Ethics Committee of Yantai Yuhuangding Hospital (Ethics No.: 2024-697). RESULTS: The patient had presented with non-obstructive azoospermia and elevated androgen sensitivity index. Ultrasound scan indicated small testicular volume and seminal vesicle atrophy. WES and bioinformatics analysis revealed abnormal amplification in the patient's AR gene. Fluorescence probe PCR and capillary electrophoresis confirmed that both the proband and his nephew had harbored 52 CAG trinucleotide repeats in exon 1 of the AR gene, confirming the diagnosis of KD. The proband's mother, elder sister, and daughter were identified as carriers of the variant, while his second elder sister did not carry the mutation. CONCLUSION As a rare X-linked recessive genetic disease, KD mainly manifests with muscle weakness, myasthenia gravis and myofascial tremor, while cases with infertility and non-obstructive azoospermia as the initial symptoms are rare and can be easily missed. Diagnosis made by genetic testing needs to be taken seriously by the clinicians.
Humans ; Male ; Bulbo-Spinal Atrophy, X-Linked/diagnosis* ; Adult ; Infertility, Male/genetics* ; Receptors, Androgen/genetics* ; Exome Sequencing ; Mutation ; Pedigree ; Trinucleotide Repeats

Amyotrophic Lateral Sclerosis (ALS) is a complex neurodegenerative disorder characterized by progressive axonopathy, jointly leading to the dying back of the motor neuron, disrupting both nerve signaling and motor control. In this review, we highlight the roles of axonopathy in ALS progression, driven by the interplay of multiple factors including defective trafficking machinery, protein aggregation, and mitochondrial dysfunction. Dysfunctional intracellular transport, caused by disruptions in microtubules, molecular motors, and adaptors, has been identified as a key contributor to disease progression. Aberrant protein aggregation involving TDP-43, FUS, SOD1, and dipeptide repeat proteins further amplifies neuronal toxicity. Mitochondrial defects lead to ATP depletion, oxidative stress, and Ca²⁺ imbalance, which are regarded as key factors underlying the loss of neuromuscular junctions and axonopathy. Mitigating these defects through interventions including neurotrophic treatments offers therapeutic potential. Collaborative research efforts aim to unravel ALS complexities, opening avenues for holistic interventions that target diverse pathological mechanisms.
Humans ; Amyotrophic Lateral Sclerosis/therapy* ; Animals ; Axons/metabolism* ; Mitochondria/metabolism* ; Motor Neurons/pathology*

BACKGROUND: Juvenile amyotrophic lateral sclerosis (JALS) is an uncommon form of amyotrophic lateral sclerosis whose age at onset (AAO) is defined as prior to 25 years. FUS mutations are the most common cause of JALS. SPTLC1 was recently identified as a disease-causative gene for JALS, which has rarely been reported in Asian populations. Little is known regarding the difference in clinical features between JALS patients carrying FUS and SPTLC1 mutations. This study aimed to screen mutations in JALS patients and to compare the clinical features between JALS patients with FUS and SPTLC1 mutations. METHODS: Sixteen JALS patients were enrolled, including three newly recruited patients between July 2015 and August 2018 from the Second Affiliated Hospital, Zhejiang University School of Medicine. Mutations were screened by whole-exome sequencing. In addition, clinical features such as AAO, onset site and disease duration were extracted and compared between JALS patients carrying FUS and SPTLC1 mutations through a literature review. RESULTS: A novel and de novo SPTLC1 mutation (c.58G>A, p.A20T) was identified in a sporadic patient. Among 16 JALS patients, 7/16 carried FUS mutations and 5/16 carried respective SPTLC1 , SETX , NEFH , DCTN1 , and TARDBP mutations. Compared with FUS mutation patients, those with SPTLC1 mutations had an earlier AAO (7.9 ± 4.6 years vs. 18.1 ± 3.9 years, P  < 0.01), much longer disease duration (512.0 [416.7-607.3] months vs. 33.4 [21.6-45.1] months, P  < 0.01), and no onset of bulbar. CONCLUSION Our findings expand the genetic and phenotypic spectrum of JALS and help to better understand the genotype-phenotype correlation of JALS.
Humans ; Amyotrophic Lateral Sclerosis/genetics* ; DNA Helicases/genetics* ; Genetic Association Studies ; Multifunctional Enzymes/genetics* ; Mutation/genetics* ; RNA Helicases/genetics* ; RNA-Binding Protein FUS/genetics* ; Serine C-Palmitoyltransferase/genetics* ; Child, Preschool ; Child ; Adolescent ; Young Adult

Humans ; Amyotrophic Lateral Sclerosis/drug therapy* ; Benzofurans/therapeutic use* ; Double-Blind Method ; Treatment Outcome

Objective: To investigate the clinical features and gene variation characteristics of children with dynein cytoplasmic 1 heavy chain 1 (DYNC1H1) gene associated spinal muscular atrophy with lower extremity predominant (SMALED) 1. Methods: The clinical data of 4 SMALED1 children admitted to Peking University First Hospital from December 2018 to May 2021, who were found to have pathogenic variation of DYNC1H1 gene through genetic testing, except for other genes known to be related to motor retardation, were retrospectively summarized to analyze the phenotype and genotype characteristics. Results: There were 3 males and 1 female. The age of onset was 1 year, 1 day, 1 day and 4 months, respectively. The age of diagnosis was 4 years and 10 months, 9 months, 5 years and 9 months, and 3 years and 1 month, respectively. The clinical manifestations were muscle weakness and muscular atrophy of lower limbs, 2 cases with foot deformity, 1 case with early non progressive joint contracture, 1 case with hip dislocation and 1 case with mental retardation. De novo heterozygous missense variations in DYNC1H1 gene were found in all 4 children. According to the rating of American College of medical genetics and genomics, they were all possible pathogenic and pathogenic variations, with p.R598C, p.P776L, p.Y1109D variations had been reported, and p.I1086R variation had not been reported. Conclusions: For those with unexplained lower limb muscle weakness, muscle atrophy, joint contracture and foot deformity, upper limb motor ability related retention, with or without mental retardation, as well as the motor ability progresses slowly, it is necessary to consider the possibility of SMALED1 and the detection of DYNC1H1 gene when necessary.
Female ; Male ; Humans ; Intellectual Disability ; Retrospective Studies ; Muscular Atrophy, Spinal/genetics* ; Lower Extremity ; Muscle Weakness ; Muscular Atrophy ; Contracture ; Cytoplasmic Dyneins/genetics*

Humans ; Muscular Atrophy, Spinal/therapy*