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Autosomal recessive spastic paraplegia 52 is caused by biallelic mutations in AP4S1 which encodes a subunit of the adaptor protein complex 4 (AP‐4). Using next‐generation sequencing, we identified three novel unrelated SPG52 patients from a cohort of patients with cerebral palsy. The discovered variants in AP4S1 lead to reduced AP‐4 complex formation in patient‐derived fibroblasts. To further understand the role of AP4S1 in neuronal development and homeostasis, we engineered the first zebrafish model of AP‐4 deficiency using morpholino‐mediated knockdown of ap4s1. In this model, we discovered several phenotypes mimicking SPG52, including altered CNS development, locomotor deficits, and abnormal neuronal excitability.

Purpose: To compare the reproducibility between contrast-enhanced digital mammography (CEDM) and magnetic resonance imaging (MRI) with the postsurgical pathologic examination. In addition, the applicability of the Breast Imaging–Reporting and Data System (BI-RADS) lexicon of MRI to CEDM was evaluated for mass lesions. Methods: A total of 62 patients with a histologically proven diagnosis of breast cancer were included in this study, for a total of 67 lesions. Fifty-nine patients underwent both methods. The reproducibility between MRI vs CEDM and the reference standard (postoperative pathology) was assessed by considering the lesion and breast size as pivotal variables. Reproducibility was evaluated by computing the concordance correlation coefficient (CCC). Bland-Altman plots were used to depict the observed pattern of agreement as well as to estimate the associated bias. Furthermore, the pattern of agreement between the investigated methods with regard to the breast lesion characterization (i.e. mass/nonmass; shape; margins; internal enhanced characteristics) was assessed by computing the Cohen kappa and its 95% confidence interval (CI). Results: The reproducibility between MRI and the reference standard and between CEDM and the reference standard showed substantial agreement, with a CCC value of 0.956 (95% CI, 0.931–0.972) and 0.950 (95% CI, 0.920–0.969), respectively. By looking at the Bland-Altman analysis, bias values of 2.344 and 1.875 mm were observed for MRI and CEDM vs reference evaluation, respectively. The agreement between MRI and CEDM is substantial with a CCC value of 0.969 (95% CI, 0.949–0.981). The Bland-Altman analysis showed bias values of −0.469 mm when comparing CEDM vs MRI. Following the Landis and Koch classification criteria, moderate agreement was observed between the two methods in describing BI-RADS descriptors of mass lesions. Conclusion: CEDM is able to measure and describe tumor masses comparably to MRI and can be used for surgical planning.

The COVID-19 pandemic represents a collective trauma that may have enduring stress effects during sensitive periods, such as pregnancy. Prenatal stress may result in epigenetic signatures of stress-related genes (e.g., the serotonin transporter gene, SLC6A4) that may in turn influence infants’ behavioral development. In April 2020, we launched a longitudinal cohort study to assess the behavioral and epigenetic vestiges of COVID-19-related prenatal stress exposure in mothers and infants. COVID-19-related prenatal stress was retrospectively assessed at birth. SLC6A4 methylation was assessed in thirteen CpG sites in mothers and infants’ buccal cells. Infants’ temperament was assessed at 3-month-age. Complete data were available from 108 mother-infant dyads. Greater COVID-19-related prenatal stress was significantly associated with higher infants’ SLC6A4 methylation in seven CpG sites. SLC6A4 methylation at these sites predicted infants’ temperament at 3 months.

Background The COVID-19 pandemic represents a collective trauma that may have enduring stress effects during sensitive periods, such as pregnancy. Prenatal stress may result in epigenetic signatures of stress-related genes (e.g., the serotonin transporter gene, SLC6A4) that may in turn influence infants’ behavioral development. Methods In April 2020, we launched a longitudinal cohort study to assess the behavioral and epigenetic vestiges of COVID-19-related prenatal stress exposure in mothers and infants. COVID-19-related prenatal stress was retrospectively assessed at birth. SLC6A4 methylation was assessed in infants’ buccal cells. Infants’ temperament was assessed at 3-month-age. Results Complete data were available from 108 mother-infant dyads. Greater COVID-19-related prenatal stress was significantly associated with higher infants’ SLC6A4 methylation (RR =.07, p =.007, B =.16 [.05;.29]). SLC6A4 methylation at these sites predicted infants’ temperament at 3 months (RR =.05, p =.027, B = -.45 [-.92;-.06]). Conclusion Indirect effects of the pandemic may alter the trajectories of behavioral development infants. Appropriate prevention and care acts need to be adopted by healthcare systems.

To determine the neuroimaging pattern of cerebellar dysplasia (CD) and other posterior fossa morphological anomalies associated with mutations in tubulin genes and to perform clinical and genetic correlations. Twenty-eight patients harbouring 23 heterozygous pathogenic variants (ten novel) in tubulin genes TUBA1A (n = 10), TUBB2B (n = 8) or TUBB3 (n = 5) were studied by a brain MRI scan performed either on a 1.5 T (n = 10) or 3 T (n = 18) MR scanner with focus on the posterior fossa. Cerebellar anomalies were detected in 24/28 patients (86%). CD was recognised in 19/28 (68%) including cortical cerebellar dysplasia (CCD) in 18/28, either involving only the cerebellar hemispheres (12/28) or associated with vermis dysplasia (6/28). CCD was located only in the right hemisphere in 13/18 (72%), including four TUBB2B-, four TUBB3- and five TUBA1A-mutated patients, while in the other five TUBA1A cases it was located only in the left hemisphere or in both hemispheres. The postero-superior region of the cerebellar hemispheres was most frequently affected. The cerebellar involvement in tubulinopathies shows specific features that may be labelled as ‘tubulin-related CD’. This pattern is unique and differs from other genetic causes of cerebellar dysplasia. • Cortical cerebellar dysplasia without cysts is suggestive of tubulin-related disorder. • Cerebellar dysplasia in tubulinopathies shows specific features labelled as ‘tubulin-related CD’. • Focal and unilateral involvement of cerebellar hemispheres has important implications for counselling.

Translational activator of cytochrome c oxidase I (TACO1) is a mitochondrial translation factor involved in mitochondria-encoded cytochrome c oxidase subunit I (MT-CO1) synthesis.1,2 Loss-of-function mutations in the TACO1 gene cause respiratory chain complex IV deficiency. Clinically heterogeneous human diseases are due to cytochrome c oxidase (COX) deficiency, ranging from Leigh syndrome to myopathy, deafness, or ataxia. Recently, 2 different TACO1 mutations have been identified in 3 families with late-onset Leigh syndrome and a leukoencephalopathy involving predominantly basal ganglia and cystic changes.3,4 Here, we report a subject carrying a novel homozygous truncating mutation in the TACO1 gene and presenting an adult-onset slowly progressive spastic paraparesis with cognitive impairment and a subcortical U-fiber leukoencephalopathy. The authors thank the patient and her family for participating in the study and Valentina Baderna for the technical support in functional studies.

CAPN1 encodes calpain-1, a large subunit of μ-calpain, a calcium-activated cysteine protease widely present in the central nervous system. Mutations in CAPN1 have recently been identified in a complicated form of Hereditary Spastic Paraplegia (HSP) with a combination of cerebellar ataxia and corticomotor tract disorder (SPG76). Therefore, CAPN1 is now considered one of those genes that clinically manifest with a spectrum of disorders ranging from spasticity to cerebellar ataxia and represent a link between Spinocerebellar Ataxia and HSP, two groups of diseases previously considered separate but sharing pathophysiological pathways. We here describe clinical and molecular findings of two Italian adult siblings affected with a pure form of HSP and harboring the novel homozygote c.959delA variant (p.Tyr320Leufs*73) in the CAPN1 gene. Although the reason why mutations in CAPN1 may cause heterogeneous clinical pictures remains speculative, our findings confirm that the spectrum of the CAPN1-linked phenotypes includes pure HSP with onset during the third decade of life. Further studies are warrantied in order to clarify the mechanism underlying the differences in CAPN1 mutation clinical expression.

This paper describes the clinical evolution and the novel genetic findings in a KIF5A mutated family previously reported as affected by spastic paraparesis only. The additional evidence we report here, a homozygous ALS2 mutation detected in the proband, and the clinical evolution observed in the affected members of the family, are in line with the evidence of an overlap between Hereditary Spastic Paraplegias and Amyotrophic Lateral Sclerosis associated with variants in these genes. The proband, a 14-years-old boy, started manifesting a pure form of HSP at age 14 months. The disease rapidly progressed to a juvenile form of ALS. This boy carries a heterozygous missense variant in KIF5A p.(Glu755Lys), inherited from the father, and a homozygous missense variant in the alsin protein encoded by the ALS2 gene p.(Pro192Leu). The father shows a family history of ALS. In the last few years, he has been developing signs and symptoms of both upper and lower motor neuron degeneration, with mild bulbar motor involvement and emotional lability. The patients described in this family, confirm the continuum and partial overlap of the two clinical entities, HSP and ALS, historically viewed as distinct entities. The genetic findings in this family further substantiate the genetic bases underlying the overlap, broadening the clinical spectrum associated with KIF5A mutations.

Antipsychotics frequently cause obesity and related metabolic disorders that current psychopharmacological/endocrinological theories do not explain consistently. An integrative/alternative theory implies metabolic alterations happening at the cellular level. Many observations in vitro and in vivo, and pivotal observations in humans, point towards chemical properties of antipsychotics, independent of receptor binding characteristics. Being amphiphilic weak bases, antipsychotics can disrupt lysosomal function, affecting cholesterol trafficking; moreover, by chemical mimicry, antipsychotics can inhibit cholesterol biosynthesis. These two molecular adverse effects may trigger a cascade of transcriptional and biochemical events, ultimately reducing available cholesterol while increasing cholesterol precursors and fatty acids. The macroscopic manifestation of these molecular alterations includes decreased high-density lipoprotein and increased very low-density lipoprotein and triglycerides that may translate into obesity and related metabolic disorders.

Aim: Recent findings show that DNA methylation is susceptible to very preterm (VPT) birth and to the experience of the early stay in the neonatal intensive care unit. The aim of the study was to compare PLAGL1 methylation between VPT and full-term (FT) infants at birth as well as between VPT infants at discharge and FT infants at birth. Methods: DNA was collected from cord blood of 56 VPT and 27 FT infants at birth and from peripheral blood in VPT infants at neonatal intensive care unit discharge. Sociodemographic and neonatal variables were considered. Results: PLAGL1 methylation at birth and at discharge were highly correlated in VPT infants. Lower methylation emerged in VPT infants at birth and discharge compared to FT counterparts. Conclusion: PLAGL1 hypomethylation emerged as a potential epigenetic mark of VPT birth. Future research is warranted to assess the functional consequences of PLAGL1 diminished methylation in VPT infants’ development.

ZFYVE26/Spastizin and SPG11/Spatacsin encode 2 large proteins that are mutated in hereditary autosomal-recessive spastic paraplegia/paraparesis (HSP) type 15 (AR-SPG15) and type 11 (AR-SPG11), respectively. We previously have reported that AR-SPG15-related ZFYVE26 mutations lead to autophagy defects with accumulation of immature autophagosomes. ZFYVE26 and SPG11 were found to be part of a complex including the AP5 (adaptor related protein complex 5) and to have a critical role in autophagic lysosomal reformation with identification of autophagic and lysosomal defects in cells with both AR-SPG15- and AR-SPG11-related mutations. In spite of these similarities between the 2 proteins, here we report that ZFYVE26 and SPG11 are differently involved in autophagy and endocytosis. We found that both ZFYVE26 and SPG11 interact with RAB5A and RAB11, 2 proteins regulating endosome trafficking and maturation, but only ZFYVE26 mutations affected RAB protein interactions and activation. ZFYVE26 mutations lead to defects in the fusion between autophagosomes and endosomes, while SPG11 mutations do not affect this step and lead to a milder autophagy defect. We thus demonstrate that ZFYVE26 and SPG11 affect the same cellular physiological processes, albeit at different levels: both proteins have a role in autophagic lysosome reformation, but only ZFYVE26 acts at the intersection between endocytosis and autophagy, thus representing a key player in these 2 processes. Indeed expression of the constitutively active form of RAB5A in cells with AR-SPG15-related mutations partially rescues the autophagy defect. Finally the model we propose demonstrates that autophagy and the endolysosomal pathway are central processes in the pathogenesis of these complicated forms of hereditary spastic paraparesis. Abbreviations: ALR, autophagic lysosome reformation; AP5, adaptor related protein complex 5; AR, autosomal-recessive; HSP, hereditary spastic paraplegia/paraparesis; ATG14, autophagy related 14; BafA, bafilomycin A1; BECN1, beclin 1; EBSS, Earle balanced salt solution; EEA1, early endosome antigen 1; EGF, epidermal growth factor; EGFR, epidermal growth factor receptor; GDP, guanosine diphosphate; GFP, green fluorescent protein; GTP, guanosine triphosphate; HSP, hereditary spastic paraplegias; LBPA, lysobisphosphatidic acid; MAP1LC3B/LC3B, microtubule associated protein 1 light chain 3 beta; MVBs, multivesicular bodies; PIK3C3, phosphatidylinositol 3-kinase, catalytic subunit type 3; PIK3R4, phosphoinositide-3-kinase regulatory subunit 4; PtdIns3P, phosphatidylinositol-3-phosphate; RFP, red fluorescent protein; RUBCN, RUN and cysteine rich domain containing beclin 1 interacting protein; shRNA, short hairpin RNA; SQSTM1/p62, sequestosome 1; TCC: thin corpus callosum; TF, transferrin; UVRAG, UV radiation resistance associated.

The original version of this article, published on 4 July 2017, unfortunately contained a mistake. The following correction has therefore been made in the original: The first name of the author Raffaella Cusmai was rendered incorrectly and has now been corrected.

Background Hereditary spastic paraplegias (HSP) are a composite and genetically heterogeneous group of conditions mainly expressed by the impairment of the central motor system (“pure” forms). The involvement of other components of the central nervous system or of other systems is described in the “complicate” forms. The definition of an investigation protocol capable, by assembling clinical and paraclinical indicators to fully represent the extent of the motor system impairment, would help both the clinical handling of these conditions and contribute to our understanding of their pathogenesis. Methods We applied a clinical and paraclinical protocol which included tools exploring motor and non motor functioning, neurophysiology and MRI to a composite cohort of 70 molecularly defined HSP patients aged 3 to 65, to define for each indicator its significance in detailing the presence and the severity of the pathology. Results Clinically increased deep tendon reflexes and lower limb (LL) weakness are constant findings in all patients. The “complicated” forms are characterized by peripheral motor impairment, cognitive and cerebellar involvement. The Spastic Paraplegia Rating Scale efficiently reflects the severity of functional problems and correlates with disease duration. Neurophysiology consistently documents the impairment of the central motor pathway to the LLs. Nevertheless, the upper extremities and sensory system involvement is a frequent finding. MRI diffusion tensor imaging (DTI) highlighted a significant alteration of FA and MD. Combining the sampling of the various portion of the cortico-spinal tract (CST) DTI consistently discriminated patients from controls. Conclusion We propose a graded clinical and paraclinical protocol for HSP phenotype definition, indicating for each tool the discriminative and descriptive capacity. Our protocol applied to 9 different forms of HSP showed that the functional impairment often extends beyond the CST. The novel DTI approach may add significant elements in disease recognition, staging and mapping.

KIF1A gene encodes the kinesin 1a protein, an axonal motor protein working in cargo transport along neurites. Variants in KIF1A were identified in different forms of neurodegenerative diseases with dominant and recessive inheritance. Homozygous recessive mutations were found in the hereditary sensory and autonomic neuropathy type 2, HSAN2 and in a recessive subtype of hereditary spastic paraparesis, SPG30. De novo heterozygous dominant variants were found both in a dominant form of SPG30 (AD-SPG30) with one single family reported and in patients with different forms of progressive neurodegenerative diseases. We report the results of a genetic screening of 192 HSP patients, with the identification of four heterozygous variants in KIF1A in four cases, two of whom with family history for the disease. Three of the four variants fall within the motor domain, a frequent target for variants related to the AD-SPG30 subtype. The fourth variant falls downstream the motor domain in a region lacking any functional domain. The KIF1A-related patients show clinical pictures overlapping the known AD-SPG30 phenotype including pure and complicated forms with few differences. Of note, one of the families, originating from the Sicily island, carries the same variant p.S69L detected in the first AD-SPG30 family of Finnish origin reported; differently from the first one, the latter family shows a wide intra-familial phenotype variability. Overall, these data reveal a very low frequency of the AD-SPG30 subtype while confirming the presence of amino acid residues in the motor domain representing preferential targets for mutations, thereby supporting their functional relevance in kinesin 1a activity.

Mutations in DDHD1 gene have been associated with the SPG28 subtype of Hereditary Spastic Paraparesis (HSP). Clinical phenotype includes axonal neuropathy, distal sensory loss, and cerebellar eye movement disturbances. We screened 96 index subjects from recessive HSP families for mutation and identified one family with two sibs carrying mutations in DDHD1 gene. Clinical, neuropsychological, and neuroimaging studies were performed, including MR spectroscopy of brain and muscle of the two mutated patients. Two novel heterozygous mutations in DDHD1 were found in the affected members of one family, with clinical features overlapping the SPG28 subtype. Of note, MR spectroscopy of brain and muscle in these patients indicated a mild deficit of brain energy metabolism in the oldest and most severely affected patient, while an impairment of energy metabolism was found in the skeletal muscle of both patients. Unlike the DDHD2 mutated patients, no evidence of lipid accumulation in the brain was found. Our data along with those previously reported suggest a dysfunction in the OXPHOS system possibly due to mitochondrial lipid content modification, which could be a central mechanism in the pathogenesis of SPG28.

Background: Homozygous and compound heterozygous mutations in SETX are associated with AOA2 disease, a recessive form of ataxia with oculomotor apraxia and neuropathy with onset of ataxia between the first and second decade of life. The majority of the AOA2 mutated cell lines tested show hypersensitivity to oxidative DNA damaging agents, with one exception. Results: We describe a patient presenting with early-onset progressive ataxia, oculomotor apraxia, axonal sensory-motor neuropathy, optic atrophy, delayed psychomotor development, and a behavior disorder. The patient carries two novel missense variants in the SETX gene. Based on the hypothesis that the patient’s clinical phenotype may represent an atypical form of the AOA2 disease, we tested the patient-derived cell line for hypersensitivity to oxidative DNA damaging agents, with negative results. Conclusions: The lack of hypersensitivity we observed may be explained either by considering the atypical clinical picture of the patient analyzed or, alternatively, by hypothesizing that the variants detected are not the cause of the observed phenotype. Consistent with the first hypothesis of an atypical AOA2 form and based on the multiple functions of senataxin reported so far, it is likely that different sets of SETX mutations / variants may have variable functional effects that still need to be functionally characterized. The possibility that the severe and complicated clinical picture presented by the patient described here represents a clinical entity differing from the known recessive ataxias should be considered as well.

Complicated hereditary spastic paraplegias (HSP) are a heterogeneous group of HSP characterized by spasticity associated with a variable combination of neurologic and extra-neurologic signs and symptoms. Among them, HSP with thin corpus callosum and intellectual disability is a frequent subtype, often inherited as a recessive trait (ARHSP-TCC). Within this heterogeneous subgroup, SPG11 and SPG15 represent the most frequent subtypes. We analyzed the mutation frequency of three genes associated with early-onset forms of ARHSP with and without TCC, CYP2U1/SPG56, DDHD2/SPG54 and GBA2/SPG46, in a large population of selected complicated HSP patients by using a combined approach of traditional-based and amplicon-based high-throughput pooled-sequencing. Three families with mutations were identified, one for each of the genes analyzed. Novel homozygous mutations were identified in CYP2U1 (c.1A>C/p.Met1?) and in GBA2 (c.2048G>C/p.Gly683Arg), while the homozygous mutation found in DDHD2 (c.1978G>C/p.Asp660His) had been previously reported in a compound heterozygous state. The phenotypes associated with the CYP2U1 and DDHD2 mutations overlap the SPG56 and the SPG54 subtypes, respectively, with few differences. By contrast, the GBA2 mutated patients show phenotypes combining typical features of both the SPG46 subtype and the recessive ataxia form, with marked intrafamilial variability thereby expanding the spectrum of clinical entities associated with GBA2 mutations. Overall, each of three genes analyzed shows a low mutation frequency in a general population of complicated HSP (

Mutations in the conserved telomere maintenance component 1 ( CTC1) gene were recently described in Coats plus syndrome and in cerebroretinal microangiopathy with calcifications and cysts. Norrie disease protein ( NDP) gene was found mutated in Norrie disease, in Familial Exudative Vitreoretinopathy, and in Coats syndrome. Here we describe a boy affected by Norrie disease who developed typical features of cerebroretinal microangiopathy with calcifications and cysts. Direct sequencing of the CTC1 and NDP genes in this patient shows the presence of compound heterozygosity for 2 mutations in CTC1 (c.775G>A, pV259M and a novel microdeletion c.1213delG) and a missense mutation in the NDP gene (c.182T>C, p.L61P). Based on these genetic findings and on the expression of both genes in endothelial cells, we postulate that microangiopathy might be a primary underlying pathologic abnormality in cerebroretinal microangiopathy with calcifications and cysts. This hypothesis is further supported by magnetic resonance imaging (MRI) data showing multiple minute calcifications in the deep gray nuclei and in terminal arteriolar zones.

Meiotic recombination requires the formation of programmed Spo11-dependent DNA double strand breaks (DSBs). In Saccharomyces cerevisiae, the Sae2 protein and the Mre11-Rad50-Xrs2 complex are necessary to remove the covalently attached Spo11 protein from the DNA ends, which are then resected by so far unknown nucleases. Here, we demonstrate that phosphorylation of Sae2 Ser-267 by cyclin-dependent kinase 1 (Cdk1) is required to initiate meiotic DSB resection by allowing Spo11 removal from DSB ends. This finding suggests that Cdk1 activity is required for the processing of Spo11-induced DSBs, thus providing a mechanism for coordinating DSB resection with progression through meiotic prophase. Furthermore, the helicase Sgs1 and the nucleases Exo1 and Dna2 participate in lengthening the 5′-3′ resection tracts during meiosis by controlling a step subsequent to Spo11 removal.