Objective: There is increasing evidence that common genetic risk factors underlie frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). Recently, mutations in the sequestosome 1 (SQSTM1) gene, which encodes p62 protein, have been reported in patients with ALS. P62 is a multifunctional adapter protein mainly involved in selective autophagy, oxidative stress response, and cell signaling pathways. The purpose of our study was to evaluate the frequency of SQSTM1 mutations in a dataset of unrelated patients with FTLD or ALS, in comparison with healthy controls and patients with Paget disease of bone (PDB). Methods:Promoter region and all exons of SQSTM1 were sequenced in a large group of subjects, including patients with FTLD or ALS, healthy controls, and patients with PDB. The clinical characteristics of patients with FTLD or ALS with gene mutations were examined. Results:We identified 6 missense mutations in the coding region of SQSTM1 in patients with either FTLD or ALS, none of which were found in healthy controls or patients with PDB. In silico analysis suggested a pathogenetic role for these mutations. Furthermore, 7 novel noncoding SQSTM1 variants were found in patients with FTLD and patients with ALS, including 4 variations in the promoter region. Conclusions:

Several polymorphisms of the hypocretin/orexin system genes were evaluated in 109 cluster headache patients and 211 controls. The 1246 G>A polymorphism of the gene was significantly different between cases and controls. Homozygosity for the G allele was associated with an increased disease risk (OR: 6.79, 95% CI, 2.25 to 22.99). The data suggest that the HCRTR2 gene or a linked locus significantly modulates the risk for cluster headache.

Our data confirm previous studies suggesting that the HCRTR2 gene or a linked locus significantly modulates the risk for CH. In addition, we suggest that the V308I substitution of the HCRTR2 may interfere with the dimerization process of the receptor, thereby influencing its functional activity.

Even though SQSTM1 gene mutations have been identified in a consistent number of patients, the etiology of Paget's disease of bone (PDB) remains in part unknown. In this study we analyzed SQSTM1 mutations in 533 of 608 consecutive PDB patients from several regions, including the high-prevalence area of Campania (also characterized by increased severity of PDB, higher number of familial cases, and peculiar phenotypic characteristics as giant cell tumor). Eleven different mutations (Y383X, P387L, P392L, E396X, M401V, M404V, G411S, D423X, G425E, G425R, and A427D) were observed in 34 of 92 (37%) and 43 of 441 (10%) of familial and sporadic PDB patients, respectively. All five patients with giant cell tumor complicating familial PDB were negative for SQSTM1 mutations. An increased heterogeneity and a different distribution of mutations were observed in southern Italy (showing 9 of the 11 mutations) than in central and northern Italy. Genotype-phenotype analysis showed only a modest reduction in age at diagnosis in patients with truncating versus missense mutations, whereas the number of affected skeletal sites did not differ significantly. Patients from Campania had the highest prevalence of animal contacts (i.e., working or living on a farm or pet ownership) without any difference between patients with or without mutation. However, when familial cases from Campania were considered, animal contacts were observed in 90% of families without mutations. Interestingly, a progressive age-related decrease in the prevalence of animal contacts, as well as a parallel increase in the prevalence of SQSTM1 mutations, was observed in most regions except in the subgroup of patients from Campania. Moreover, patients reporting animal contacts showed an increased number of affected sites (2.54 AE 2.0 versus 2.19 AE 1.9, p < .05) over patients without animal contacts. This difference also was evidenced in the subgroup of patients with SQSTM1 mutations (3.84 AE 2.5 versus 2.76 AE 2.2, p < .05). Overall, these data suggest that animal-related factors may be important in the etiology of PDB and may interact with SQSTM1 mutations in influencing disease severity. ß

IMPORTANCE Juvenile amyotrophic lateral sclerosis (ALS) is a rare form of ALS characterized by age of symptom onset less than 25 years and a variable presentation.OBJECTIVE To identify the genetic variants associated with juvenile ALS. DESIGN, SETTING, AND PARTICIPANTSIn this multicenter family-based genetic study, trio whole-exome sequencing was performed to identify the disease-associated gene in a case series of unrelated patients diagnosed with juvenile ALS and severe growth retardation. The patients and their family members were enrolled at academic hospitals and a government research facility between March 1, 2016, and March 13, 2020, and were observed until October 1, 2020. Whole-exome sequencing was also performed in a series of patients with juvenile ALS. A total of 66 patients with juvenile ALS and 6258 adult patients with ALS participated in the study. Patients were selected for the study based on their diagnosis, and all eligible participants were enrolled in the study. None of the participants had a family history of neurological disorders, suggesting de novo variants as the underlying genetic mechanism. MAIN OUTCOMES AND MEASURESDe novo variants present only in the index case and not in unaffected family members. RESULTSTrio whole-exome sequencing was performed in 3 patients diagnosed with juvenile ALS and their parents. An additional 63 patients with juvenile ALS and 6258 adult patients with ALS were subsequently screened for variants in the SPTLC1 gene. De novo variants in SPTLC1 (p.Ala20Ser in 2 patients and p.Ser331Tyr in 1 patient) were identified in 3 unrelated patients diagnosed with juvenile ALS and failure to thrive. A fourth variant (p.Leu39del) was identified in a patient with juvenile ALS where parental DNA was unavailable. Variants in this gene have been previously shown to be associated with autosomal-dominant hereditary sensory autonomic neuropathy, type 1A, by disrupting an essential enzyme complex in the sphingolipid synthesis pathway.CONCLUSIONS AND RELEVANCE These data broaden the phenotype associated with SPTLC1 and suggest that patients presenting with juvenile ALS should be screened for variants in this gene.

Our data suggest that cluster headache is associated with the ADH4 gene or a linked locus. Additional studies are warranted to elucidate the role of this gene in the etiopathogenesis of the disease.

Hereditary spastic paraplegia (HSP) refers to a group of genetically heterogeneous neurodegenerative motor neuron disorders characterized by progressive age-dependent loss of corticospinal motor tract function, lower limb spasticity, and weakness. Recent clinical use of next generation sequencing (NGS) methodologies suggests that they facilitate the diagnostic approach to HSP, but the power of NGS as a first-tier diagnostic procedure is unclear. The larger-than-expected genetic heterogeneity—there are over 80 potential disease-associated genes—and frequent overlap with other clinical conditions affecting the motor system make a molecular diagnosis in HSP cumbersome and time consuming. In a single-center, cross-sectional study, spanning 4 years, 239 subjects with a clinical diagnosis of HSP underwent molecular screening of a large set of genes, using two different customized NGS panels. The latest version of our targeted sequencing panel (SpastiSure3.0) comprises 118 genes known to be associated with HSP. Using an in-house validated bioinformatics pipeline and several in silico tools to predict mutation pathogenicity, we obtained a positive diagnostic yield of 29% (70/239), whereas variants of unknown significance (VUS) were found in 86 patients (36%), and 83 cases remained unsolved. This study is among the largest screenings of consecutive HSP index cases enrolled in real-life clinical-diagnostic settings. Its results corroborate NGS as a modern, first-step procedure for molecular diagnosis of HSP. It also disclosed a significant number of new mutations in ultra-rare genes, expanding the clinical spectrum, and genetic landscape of HSP, at least in Italy.

Altered gene expression occurs in central nervous system disorders, including Alzheimer's disease (AD). Transcription factor Sp1 (specificity protein 1) can regulate the expression of several AD-related proteins, including amyloid-β protein precursor and tau. Sp1 is regulated by oxidative stress, and Sp1 mRNA was found to be upregulated in AD cortex and hippocampus. The distribution of three single nucleotide polymorphisms (SNPs), including rs7300593, rs17695156, and rs12821290, covering 100% Sp1 genetic variability, has been determined in a population of 393 AD patients as compared with 412 controls. In addition, expression analysis of Sp1 and its regulatory microRNAs (hsa-miR-29b and hsa-miR-375) has been performed in peripheral blood mononuclear cells (PBMCs), together with Sp1 protein analysis. No differences in all three SNP distributions were observed in AD patients as compared with controls. Stratifying according to gender, a significantly decreased frequency of Sp1 rs17695156 T allele was observed in male patients versus male controls. Significantly increased Sp1 relative expression levels were observed in PBMCs from AD patients as compared with controls. Western blot analysis paralleled mRNA increase in AD patients versus controls and correlated positively with Sp1 mRNA levels. Significantly decreased relative expression levels of hsa-miR-29b, but not of hsa-miR-375, were observed in AD patients versus controls and correlated negatively with Sp1 mRNA levels. According to these results, Sp1 and its regulatory hsa-miR-29b are deregulated in AD patients, possibly leading to aberrant production of downstream target genes involved in the pathogenesis. Moreover, Sp1 rs176951056 T allele is likely a protective factor in the male population.