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Item does not contain fulltext PURPOSE: Hereditary spastic paraplegia type 4 is extremely variable in age at onset; the same variant can cause onset at birth or in the eighth decade. We recently discovered that missense variants in SPAST, which influences microtubule dynamics, are associated with earlier onset and more severe disease than truncating variants, but even within the early and late-onset groups there remained significant differences in onset. Given the rarity of the condition, we adapted an extreme phenotype approach to identify genetic modifiers of onset. METHODS: We performed a genome-wide association study on 134 patients bearing truncating pathogenic variants in SPAST, divided into early- and late-onset groups (aged ≤15 and ≥45 years, respectively). A replication cohort of 419 included patients carrying either truncating or missense variants. Finally, age at onset was analyzed in the merged cohort (N = 553). RESULTS: We found 1 signal associated with earlier age at onset (rs10775533, P = 8.73E-6) in 2 independent cohorts and in the merged cohort (N = 553, Mantel-Cox test, P < .0001). Western blotting in lymphocytes of 20 patients showed that this locus tends to upregulate SARS2 expression in earlier-onset patients. CONCLUSION: SARS2 overexpression lowers the age of onset in hereditary spastic paraplegia type 4. Lowering SARS2 or improving mitochondrial function could thus present viable approaches to therapy.

ATL1-related spastic paraplegia SPG3A is a pure form of hereditary spastic paraplegia. Rare complex phenotypes have been described, but few data concerning cognitive evaluation or molecular imaging of these patients are available. We relate a retrospective collection of patients with SPG3A from the Neurology Department of Nancy University Hospital, France. For each patient were carried out a

Biallelic mutations in AP5Z1 are known to cause a rare, autosomal recessive, complex form of hereditary spastic paraplegia (HSP) referred to as SPG48 (MIM#613647)[1]. To date, only 11 SPG48 cases have been reported. The clinical spectrum of SPG48 is complex and heterogeneous, presenting with neuropathy, ataxia, dystonia and parkinsonism in addition to the spastic paraplegia (SP). AP5Z1 codes for the ζsubunit of the AP-5 complex, implicated in vesicular-mediated intracellular sorting and trafficking of cargo proteins[1] and functional studies demonstrate accumulation of multilamellar structures(endolysosomes) in SPG48 skin fibroblasts[2].

Introduction Des variants dans un nombre croissant de genes sont impliques dans les paraparesies spastiques hereditaires (PSH). Le sequencage haut debit de panels multi-genes permet leur etude ciblee en un temps. Objectifs Cette etude avait pour objectif de decrire le taux de resolution diagnostique et la distribution des genes causaux identifies avec notre panel de genes. Patients et methodes Les resultats des cas index PSH testes entre decembre 2013 et juillet 2019 avec le panel de genes developpe a l’institut du cerveau et utilise a l’hopital de la Pitie-Salpetriere (Paris, France) ont ete recuperes. La version initiale du panel couvrait 65 genes. Le caractere causal des variants etait determine suivant les criteres ACMG et leur presence confirmee par une deuxieme analyse ciblee (Sanger ou MLPA). Resultats Le gene causal a ete identifie chez 472/1550 patients (30,5 %) parmi 35 des 65 genes analyses. Un variant supplementaire a ete identifie avec l’ajout de 7 genes pour les 373 derniers patients testes. Les genes les plus frequemment retrouves etaient de transmission autosomique dominante (60,4 %) avec SPAST (9,1 % des patients), KIF1A (2,2 %) et ATL1 (2,2 %) et recessive (39,4 %) avec SPG7 (4,8 %) et SPG11 (1,7 %). Les variants structuraux representaient 6,0 % des variants pathogenes (1,9 % des patients). Discussion Il s’agit de la plus grande serie validant les performances diagnostiques courantes d’un panel de genes dans les PSH. L’etude d’un grand nombre de genes en une analyse facilite la mise en evidence de genes rares et varies. La couverture de sequencage optimisee permettait la detection de variants structuraux, critique en raison de leur proportion non negligeable. Conclusion Les panels sont performants comme premiere exploration genetique des PSH. La connaissance de la repartition des genes causaux va permettre de renforcer la recherche sur les formes affectant le plus grand nombre de patients.

IF 10.292; International audience; The hereditary spastic paraplegias are an expanding and heterogeneous group of disorders characterized by spasticity in the lower limbs. Plasma biomarkers are needed to guide the genetic testing of spastic paraplegia. Spastic paraplegia type 5 (SPG5) is an autosomal recessive spastic paraplegia due to mutations in CYP7B1, which encodes a cytochrome P450 7α-hydroxylase implicated in cholesterol and bile acids metabolism. We developed a method based on ultra-performance liquid chromatography electrospray tandem mass spectrometry to validate two plasma 25-hydroxycholesterol (25-OHC) and 27-hydroxycholesterol (27-OHC) as diagnostic biomarkers in a cohort of 21 patients with SPG5. For 14 patients, SPG5 was initially suspected on the basis of genetic analysis, and then confirmed by increased plasma 25-OHC, 27-OHC and their ratio to total cholesterol. For seven patients, the diagnosis was initially based on elevated plasma oxysterol levels and confirmed by the identification of two causal CYP7B1 mutations. The receiver operating characteristic curves analysis showed that 25-OHC, 27-OHC and their ratio to total cholesterol discriminated between SPG5 patients and healthy controls with 100% sensitivity and specificity. Taking advantage of the robustness of these plasma oxysterols, we then conducted a phase II therapeutic trial in 12 patients and tested whether candidate molecules (atorvastatin, chenodeoxycholic acid and resveratrol) can lower plasma oxysterols and improve bile acids profile. The trial consisted of a three-period, three-treatment crossover study and the six different sequences of three treatments were randomized. Using a linear mixed effect regression model with a random intercept, we observed that atorvastatin decreased moderately plasma 27-OHC (∼30%, P < 0.001) but did not change 27-OHC to total cholesterol ratio or 25-OHC levels. We also found an abnormal bile acids profile in SPG5 patients, with significantly decreased total serum bile acids associated with a relative decrease of ursodeoxycholic and lithocholic acids compared to deoxycholic acid. Treatment with chenodeoxycholic acid restored bile acids profile in SPG5 patients. Therefore, the combination of atorvastatin and chenodeoxycholic acid may be worth considering for the treatment of SPG5 patients but the neurological benefit of these metabolic interventions remains to be evaluated in phase III therapeutic trials using clinical, imaging and/or electrophysiological outcome measures with sufficient effect sizes. Overall, our study indicates that plasma 25-OHC and 27-OHC are robust diagnostic biomarkers of SPG5 and shall be used as first-line investigations in any patient with unexplained spastic paraplegia.

Chondrosarcomas are primary cancers of cartilaginous tissue with highly contrasting prognoses. These tumors are defined by recurrent mutations in the IDH genes and other genetic alterations including inactivation of CDKN2A and COL2A1; however, these have no clinical value. Here we use multi-omics molecular profiles from a series of cartilage tumors and find an mRNA classification that identifies two subtypes of chondrosarcomas defined by a balance in tumor differentiation and cell cycle activation. The microRNA classification reveals the importance of the loss of expression of the 14q32 locus in defining the level of malignancy. Finally, DNA methylation is associated with IDH mutations. We can use the multi-omics classifications to predict outcome. We propose an mRNA-only classifier to reproduce the integrated multi-omics classification, and its application to relapsed tumor samples shows the progressive nature of the classification. Thus, it may be possible to use mRNA-based signatures to detect patients with high-risk chondrosarcomas., Chondrosarcomas are heterogenous tumours of the bone cartilage and have highly variable prognoses. Here, the authors perform a multi-omics analysis, revealing molecular features that can stratify clinical outcomes.

Le paraplegie spastiche ereditarie (PSE), o malattia di Strumpell-Lorrain, sono caratterizzate da una spasticita e debolezza progressive degli arti inferiori. Esse sono legate a una degenerazione distale retrograda e bilaterale dei fasci corticospinali. L’evoluzione e, in genere, lenta e graduale, con notevoli variazioni relativamente a eta di insorgenza e gravita. Si distinguono le forme pure dalle forme complesse. Le PSE sono trasmesse secondo tutte le modalita ereditarie e oltre 70 geni sono stati successivamente localizzati o identificati. Diversi meccanismi fisiopatologici sono stati via via individuati, tra cui le alterazioni del trasporto intracellulare, le anomalie dello sviluppo assonale e della mielina, le disfunzioni mitocondriali e il metabolismo anomalo di alcuni lipidi. Questo articolo si propone di riassumere le attuali conoscenze, in continua evoluzione, nel vasto campo delle PSE.

Supplemental Digital Content is available in the text, Rationale: Hereditary spastic paraplegia (HSP) is a heterogeneous group of diseases little known in clinical practice due to its low prevalence, slow progression, and difficult diagnosis. This results in an underestimation of HSP leading to belated diagnosis and management. In depth diagnosis is based on clinical presentation and identification of genomic mutations. We describe the clinical presentation and pathogeny of HSP through a report of a case due to a novel mutation of the REEP1 gene (SPG31). Patient concerns: A 64-year-old woman presented gait disturbances due to spasticity of the lower limbs progressing since her third decade. Previous investigations failed to find any cause. Interventions: DNA analysis was performed to search for HSP causing mutations. Diagnoses: A novel heterozygote mutation (c.595 + 1G>A) of the REEP1 gene, within the splice site of intron 6, was discovered. This nucleotide change causes exon 6 skipping leading to frame shift and a truncated transcript identified by complementary DNA sequencing of reverse transcription polymerase chain reaction products. Outcomes: REEP1 is a known protein predominantly located in the upper motor neurons. Mutation of REEP1 primary affects the longest axons explaining predominance of pyramidal syndrome on lower limbs. Lessons: Slow progressive pyramidal syndrome of the lower limbs should elicit a diagnosis of HSP. We describe a novel mutation of the REEP1 gene causing HSP. Pathogeny is based on resulting abnormal REEP1 protein which is involved in the development of longest axons constituting the corticospinal tracts.

Syndromic obesity is defined by the association of obesity with one or more feature(s) including developmental delay, dysmorphic traits, and/or congenital malformations. Over 25 syndromic forms of obesity have been identified. However, most cases remain of unknown etiology. The aim of this study was to identify new candidate loci associated with syndromic obesity to find new candidate genes and to better understand molecular mechanisms involved in this pathology. We performed oligonucleotide microarray-based comparative genomic hybridization in a cohort of 100 children presenting with syndromic obesity of unknown etiology, after exhaustive clinical, biological, and molecular studies. Chromosomal copy number variations were detected in 42% of the children in our cohort, with 23% of patients with potentially pathogenic copy number variants. Our results support that chromosomal rearrangements are frequently associated with syndromic obesity with a variety of contributory genes having relevance to either obesity or developmental delay. A list of inherited or apparently de novo duplications and deletions including their enclosed genes and not previously linked to syndromic obesity was established. Proteins encoded by several of these genes are involved in lipid metabolism (ACOXL, MSMO1, MVD, and PDZK1) linked with nervous system function (BDH1 and LINGO2), neutral lipid storage (PLIN2), energy homeostasis and metabolic processes (CDH13, CNTNAP2, CPPED1, NDUFA4, PTGS2, and SOCS6).

PTEN plays a well-established role in the negative regulation of the PI3K pathway, which is frequently activated in several cancer types, including breast cancer. A nuclear function in the maintenance of chromosomal stability has been proposed for PTEN but is yet to be clearly defined. In order to improve understanding of the role of PTEN in mammary tumorigenesis in terms of a possible gene dosage effect, its PI3K pathway function and its association with p53, we undertook comprehensive analysis of PTEN status in 135 sporadic invasive ductal carcinomas. Four PTEN status groups were defined; complete loss (19/135, 14%), reduced copy number (19/135, 14%), normal (86/135, 64%) and complex (11/135, 8%). Whereas the PTEN complete loss status was significantly associated with estrogen receptor (ER) negativity (p=0.006) and in particular the basal-like phenotype (p

Introduction Les paraparesies spastiques hereditaires sont cliniquement et genetiquement heterogenes. SPG11, la plus frequente des formes autosomiques recessives, appartient aux formes complexes, debutant precocement, avec corps calleux fin et deficience intellectuelle. Objectifs Notre objectif est de mieux definir l’histoire naturelle de la maladie, de preciser les caracteristiques cliniques et paracliniques de la maladie en vue de mettre en place un suivi longitudinal. Methodes Nous avons analyse les donnees cliniques et paracliniques de 220 patients, connus de notre consultation du CRMR (n = 48) et/ou du laboratoire realisant l’analyse en diagnostic (n = 62) ainsi qu’en recherche dans le reseau SPATAX (n = 110). Resultats Les caracteristiques cliniques de 98 patients etaient disponibles. Au total, 42 % (35/83) etaient porteurs de mutations homozygotes liees a une consanguinite, 12,5 % des patients etaient d’origine francaise. L’âge de debut moyen etait de 13,4 ± 5,3 ans [1–28]. Le Spinocerebellar Disability Functional Score (score SDFS) moyen etait a 4/7 (aide unilaterale a la marche) avec un âge moyen a l’examen de 25,5 ± 7,7 ans [10–49]. Au total, 23 patients etaient au fauteuil avec un âge moyen de 23 ans [16–36]. Discussion SPG11 est une PSH complexe debutant le plus souvent dans l’enfance, parfois par un retard des acquisitions puis l’apparition du syndrome pyramidal accompagne souvent d’un syndrome cerebelleux. L’evolution severe de la maladie semble liee a une atteinte progressive de la corne anterieure. Conclusion Cette serie de patients SPG11 vient enrichir les connaissances cliniques, en vue de pouvoir preciser l’evolution souvent severe, qui semble correlee a une atteinte progressive du premier et deuxieme motoneurones.

PTEN plays a well-established role in the negative regulation of the PI3K pathway, which is frequently activated in several cancer types, including breast cancer. A nuclear function in the maintenance of chromosomal stability has been proposed for PTEN but is yet to be clearly defined. In order to improve understanding of the role of PTEN in mammary tumorigenesis in terms of a possible gene dosage effect, its PI3K pathway function and its association with p53, we undertook comprehensive analysis of PTEN status in 135 sporadic invasive ductal carcinomas. Four PTEN status groups were defined; complete loss (19/135, 14%), reduced copy number (19/135, 14%), normal (86/135, 64%) and complex (11/135, 8%). Whereas the PTEN complete loss status was significantly associated with estrogen receptor (ER) negativity (p=0.006) and in particular the basal-like phenotype (p0.0001), a reduced PTEN copy number was not associated with hormone receptor status or a particular breast cancer subtype. Overall, PI3K pathway alteration was suggested to be involved in 59% (79/134) of tumors as assessed by human epidermal growth factor receptor 2 overexpression, PIK3CA mutation or a complete loss of PTEN. A complex PTEN status was identified in a tumor subgroup which displayed a specific, complex DNA profile at the PTEN locus with a strikingly similar highly rearranged pan-genomic profile. All of these tumors had relapsed and were associated with a poorer prognosis in the context of node negative disease (p=1.4 × 10(-13) ) thus may represent a tumor subgroup with a common molecular alteration which could be targeted to improve clinical outcome.