Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by the degeneration of motor neurons. Genetic factors play a key role in ALS, and identifying variants that contribute to ALS susceptibility is an important step toward understanding the etiology of the disease. The frequency of protein altering variants in ALS patients has been extensively investigated in populations of different ethnic origin. To further delineate the genetic architecture of the Hungarian ALS patients, we aimed to detect potentially damaging variants in major and minor ALS genes and in genes related to other neurogenetic disorders. A combination of repeat-sizing of C9orf72 and next-generation sequencing (NGS) was used to comprehensively assess genetic variations in 107 Hungarian patients with ALS. Variants in major ALS genes were detected in 36.45% of patients. As a result of repeat sizing, pathogenic repeat expansions in the C9orf72 gene were detected in 10 patients (9.3%). According to the NGS results, the most frequently mutated genes were NEK1 (5.6%), NEFH , SQSTM1 (3.7%), KIF5A , SPG11 (2.8%), ALS2 , CCNF , FUS , MATR3 , TBK1 , and UBQLN2 (1.9%). Furthermore, potentially pathogenic variants were found in GRN and SIGMAR1 genes in single patients. Additional 33 novel or rare known variants were detected in minor ALS genes, as well as 48 variants in genes previously linked to other neurogenetic disorders. The latter finding supports the hypothesis that common pathways in different neurodegenerative diseases may contribute to the development of ALS. While the disease-causing role of several variants identified in this study has previously been established, other variants may show reduced penetrance or may be rare benign variants. Our findings highlight the necessity for large-scale multicenter studies on ALS patients to gain a more accurate view of the genetic pattern of ALS.

Amyotrophic lateral sclerosis (ALS) is a lethal multisystem neurodegenerative disease associated with progressive loss of motor neurons, leading to death. Not only is the clinical picture of ALS heterogenous, but also the pain sensation due to different types of pain involvement. ALS used to be considered a painless disease, but research has been emerging and depicting a more complex pain representation in ALS. Pain has been detected even a couple years before the symptomatic stage of ALS, referring to primary pain associated with muscle denervation, although secondary pain due to nociceptive causes is also a part of the clinical picture. A new non-contact dying-back injury mechanism theory of ALS recently postulated that the irreversible intrafusal proprioceptive Piezo2 microinjury could be the primary damage, with underlying genetic and environmental risk factors. Moreover, this Piezo2 primary damage is also proposed to dysregulate the primary pain pathways in the spinal dorsal horn in ALS due to the lost imbalanced subthreshold Ca2+ currents, NMDA activation and lost L-type Ca2+ currents, leading to the lost activation of wide dynamic range neurons. Our investigation is the first to show that the likely pathogenic variants of the Cav1.3 encoding CACNA1D gene may play a role in ALS pathology and the associated dysregulation or loss of the pain sensation. Furthermore, our reanalysis also shows that the SCN1A gene might also contribute to the dysregulated pain sensation in ALS. Finally, the absence of pathogenic variants of Piezo2 points toward the new non-contact dying-back injury mechanism theory of ALS. However, molecular and genetic investigations are needed to identify the functionally diverse features of this proposed novel critical pathway.

Introduction Mutations in the angiogenin ( ANG ) gene are known to be associated with both familial and sporadic amyotrophic lateral sclerosis (ALS). The majority of disease‐causing mutations of ANG result in loss of either ribonucleolytic activity, nuclear translocation activity or both. Methods We sequenced ANG gene from a total of 136 sporadic ALS patients and 112 healthy controls of Hungarian origin. To elucidate the role of the R33W mutation in the disease mechanism, computational, and functional analyses were performed. Results Mutation screening revealed a mutation located in the signal peptide (M‐24I) and two mutations that affect the mature protein (R33W, V103I). The R33W mutation, which has not been previously detected in ALS patients, affects the key amino acid of the nuclear translocation signal of the ANG protein. Molecular dynamics simulations suggested that the R33W mutation results in partial loss of ribonucleolytic activity and reduced nuclear translocation activity. The ribonucleolytic assay and nuclear translocation assay of the R33W ANG protein confirmed the molecular dynamics results. Conclusions In the Hungarian ALS population, the observed frequency of ANG mutations was 2.9%, which is higher than previously reported for sporadic cohorts. The evidence from computational and functional analyses support the deleterious effect of the novel R33W variant detected in this study.

Dystonia is a rare movement disorder which is characterized by sustained or intermittent muscle contractions causing abnormal and often repetitive movements, postures, or both. The two most common forms of adult-onset focal dystonia are cervical dystonia (CD) and benign essential blepharospasm (BSP). A total of 121 patients (CD, 74; BSP, 47) were included in the study. The average age of the patients was 64 years. For the next-generation sequencing (NGS) approach, 30 genes were selected on the basis of a thorough search of the scientific literature. Assessment of 30 CD- and BSP-associated genes from 121 patients revealed a total of 209 different heterozygous variants in 24 genes. Established clinical and genetic validity was determined for nine heterozygous variations (three likely pathogenic and six variants of uncertain significance). Detailed genetic examination is an important part of the work-up for focal dystonia forms. To our knowledge, our investigation is the first such study to be carried out in the Middle-European region.