Biancheri R.,Child Neurology and Psychiatry Unit |
Rosano C.,Instituto Nazionale per la Ricerca sul Cancro IST |
Denegri L.,Child Neurology and Psychiatry Unit |
Lamantea E.,C Besta Neurological Institute |
And 4 more authors.
European Journal of Human Genetics | Year: 2013
Homozygous or compound heterozygous mutations in the GJC2 gene, encoding the gap junction protein connexin47 (Cx47), cause the autosomal recessive hypomyelinating Pelizaeus-Merzbacher-like disease (PMLD1, MIM 608804). Although clinical and neuroradiological findings resemble those of the classic Pelizaeus-Merzbacher disease, PMLD patients usually show a greater level of cognitive and motor functions. Unpredictably a homozygous missense GJC2 mutation (p.Glu260Lys) was found in a patient presenting with a very severe clinical picture characterised by congenital nystagmus and severe neurological impairment. Also magnetic resonance imaging was unusually severe, showing an abnormal supra-and infratentorial white matter involvement extending to the spinal cord. The novel p.Glu260Lys (c.778G>A) mutation, occurring in a highly conserved motif (SRPTEK) of the Cx47 extracellular loop-2 domain, was predicted, by modelling analysis, to break a 'salt bridge network', crucial for a proper connexin-connexin interaction to form a connexon, thus hampering the correct formation of the connexon pore. The same structural analysis, extended to the previously reported missense mutations, predicted that most changes were expected to have less severe impact on protein functions, correlating with the mild PMLD1 form of the patients. Our study expands the spectrum of PMLD1 and provides evidence that the extremely severe clinical and neuroradiological PMLD1 form of our patient likely correlates with the predicted impairment of gap junction channel assembly resulting from the detrimental effect of the new p.Glu260Lys mutant allele on Cx47 protein. © 2013 Macmillan Publishers Limited. All rights reserved.
PubMed | Child Neurology and Psychiatry Unit, Catholic University, IRCCS Eugenio Medea and Bambino Gesu Childrens Hospital
Type: Journal Article | Journal: PloS one | Year: 2015
Neurodevelopmental and cognitive difficulties are known to occur frequently in boys with Duchenne muscular dystrophy but so far none of the published studies have reported both early neurodevelopmental assessments and cognitive tests in the same cohort. The aim of the present longitudinal study was to establish the correlation between early neurodevelopmental assessments performed in preschool boys and the cognitive scales performed at school age or later.We performed cognitive tests at school age (mean age 5.7 year 1.7 SD) (69 months+19 SD) in a cohort of Duchenne boys, previously assessed using the Griffiths scales before the age of 4 years (mean age when the Griffiths scales were performed 30 months 8.9 SD).The range of total Developmental quotients on the Griffiths ranged between 56 and 116 (mean 89 15.6 SD). The total Intelligence Quotients on the Wechsler scales ranged between 35 and 119 (mean 87 17.2 SD). There was a significant correlation between the findings on the two scales. P = <0.0001. When we subdivided the cohort according to site of mutations, there was a difference between boys with mutations upstream exon 44 and those with mutations in exon 44-45 affecting Dp140 on both Developmental and Intelligence Quotient (p 0.01 and p 0,003 respectively).Our results confirm that Duchenne boys tend to slightly underperform on both neurodevelopmental and cognitive assessments. Early neurodevelopmental findings correlated with the cognitive results obtained at school age with a clear concordance between subscales exploring similar domains on the two scales.
PubMed | University of Padua, University of Genoa, Child Neurology and Psychiatry Unit, CNR Institute of Neurological Sciences and 12 more.
Type: Journal Article | Journal: PloS one | Year: 2016
The role of timed items, and more specifically, of the time to rise from the floor, has been reported as an early prognostic factor for disease progression and loss of ambulation. The aim of our study was to investigate the possible effect of the time to rise from the floor test on the changes observed on the 6MWT over 12 months in a cohort of ambulant Duchenne boys.A total of 487 12-month data points were collected from 215 ambulant Duchenne boys. The age ranged between 5.0 and 20.0 years (mean 8.48 2.48 DS).The results of the time to rise from the floor at baseline ranged from 1.2 to 29.4 seconds in the boys who could perform the test. 49 patients were unable to perform the test at baseline and 87 at 12 month The 6MWT values ranged from 82 to 567 meters at baseline. 3 patients lost the ability to perform the 6mwt at 12 months. The correlation between time to rise from the floor and 6MWT at baseline was high (r = 0.6, p<0.01).Both time to rise from the floor and baseline 6MWT were relevant for predicting 6MWT changes in the group above the age of 7 years, with no interaction between the two measures, as the impact of time to rise from the floor on 6MWT change was similar in the patients below and above 350 m. Our results suggest that, time to rise from the floor can be considered an additional important prognostic factor of 12 month changes on the 6MWT and, more generally, of disease progression.
PubMed | University of Padua, Child Neurology and Psychiatry Unit, IRCCS Eugenio Medea, Catholic University and 10 more.
Type: | Journal: PLoS currents | Year: 2015
The Performance of Upper Limb (PUL) test was specifically developed for the assessment of upper limbs in Duchenne muscular dystrophy (DMD). The first published data have shown that early signs of involvement can also be found in ambulant DMD boys. The aim of this longitudinal Italian multicentric study was to evaluate the correlation between the 6 Minute Walk Test (6MWT) and the PUL in ambulant DMD boys. Both 6MWT and PUL were administered to 164 ambulant DMD boys of age between 5.0 and 16.17 years (mean 8.82). The 6 minute walk distance (6MWD) ranged between 118 and 557 (mean: 376.38, SD: 90.59). The PUL total scores ranged between 52 and 74 (mean: 70.74, SD: 4.66). The correlation between the two measures was 0.499. The scores on the PUL largely reflect the overall impairment observed on the 6MWT but the correlation was not linear. The use of the PUL appeared to be less relevant in the very strong patients with 6MWD above 400 meters, who, with few exceptions had near full scores. In patients with lower 6MWD the severity of upper limb involvement was more variable and could not always be predicted by the 6MWD value or by the use of steroids. Our results confirm that upper limb involvement can already be found in DMD boys even in the ambulant phase.
Cellini E.,University of Florence |
Vignoli A.,University of Milan |
Pisano T.,University of Florence |
Falchi M.,University of Florence |
And 6 more authors.
Developmental Medicine and Child Neurology | Year: 2016
Aim: Forkhead Box G1 (FOXG1) syndrome is a developmental encephalopathy characterized by postnatal microcephaly, structural brain abnormalities, facial dysmorphisms, severe delay with absent language, defective social interactions, and epilepsy. Abnormal movements in FOXG1 syndrome have often been mentioned but not characterized. Method: We clinically assessed and analysed video recordings of eight patients with different mutations or copy number variations affecting the FOXG1 gene and describe the peculiar pattern of the associated movement disorder. Results: The age of the patients in the study ranged from 2 to 17 years old (six females, two males). They had severe epilepsy and exhibited a complex motor disorder including various combinations of dyskinetic and hyperkinetic movements featuring dystonia, chorea, and athetosis. The onset of the movement disorder was apparent within the first year of life, reached its maximum expression within months, and then remained stable. Interpretation: A hyperkinetic-dyskinetic movement disorder emerges as a distinctive feature of the FOXG1-related phenotype. FOXG1 syndrome is as an epileptic-dyskinetic encephalopathy whose clinical presentation bears similarities with ARX- and STXBP1-gene related encephalopathies. What this paper adds: Assessment of movement disorder in patients with FOXG1 mutations or copy number variations. FOXG1 syndrome can be defined as an epileptic-dyskinetic encephalopathy. This article is commented on by Parker on page 15 of this issue. Developmental Medicine and Child Neurology © 2016 Mac Keith Press.
PubMed | Child Neurology and Psychiatry Unit, University of Florence, University of Trieste, Neuroradiology Unit and University of Milan
Type: Case Reports | Journal: Developmental medicine and child neurology | Year: 2016
Forkhead BoxG1 (FOXG1) syndrome is a developmental encephalopathy characterized by postnatal microcephaly, structural brain abnormalities, facial dysmorphisms, severe delay with absent language, defective social interactions, and epilepsy. Abnormal movements in FOXG1 syndrome have often been mentioned but not characterized.We clinically assessed and analysed video recordings of eight patients with different mutations or copy number variations affecting the FOXG1 gene and describe the peculiar pattern of the associated movement disorder.The age of the patients in the study ranged from 2 to 17years old (six females, two males). They had severe epilepsy and exhibited a complex motor disorder including various combinations of dyskinetic and hyperkinetic movements featuring dystonia, chorea, and athetosis. The onset of the movement disorder was apparent within the first year of life, reached its maximum expression within months, and then remained stable.A hyperkinetic-dyskinetic movement disorder emerges as a distinctive feature of the FOXG1-related phenotype. FOXG1 syndrome is as an epileptic-dyskinetic encephalopathy whose clinical presentation bears similarities with ARX- and STXBP1-gene related encephalopathies.
Marini C.,University of Florence |
Mei D.,University of Florence |
Parmeggiani L.,Azienda Sanitaria di Bolzano |
Norci V.,University of Florence |
And 9 more authors.
Neurology | Year: 2010
Objective: To explore the causative role of PCDH19 gene (Xq22) in female patients with epilepsy. Methods: We studied a cohort of 117 female patients with febrile seizures (FS) and a wide spectrum of epilepsy phenotypes including focal and generalized forms with either sporadic or familial distribution. Results: PCDH19 screening showed point mutations in 13 probands (11%). Mean age at seizure onset was 8.5 months; 8 patients (62%) presented with FS, 4 (33%) with cluster of focal seizures, and 1 with de novo status epilepticus (SE). Subsequent seizure types included afebrile tonic-clonic, febrile, and afebrile SE, absences, myoclonic, and focal seizures. Seven patients (54%) had a clinical diagnosis consistent with Dravet syndrome (DS); 6 (46%) had focal epilepsy. In most patients, seizures were particularly frequent at onset, manifesting in clusters and becoming less frequent with age. Mental retardation was present in 11 patients, ranging from mild (7; 64%) to moderate (1; 9%) to severe (3; 27%). Five patients (38%) had autistic features in association to mental retardation. Mutations were missense (6), truncating (2), frameshift (3), and splicing (2). Eleven were new mutations. Mutations were inherited in 3 probands (25%): 2 from apparently unaffected fathers and 1 from a mother who had had generalized epilepsy. Conclusions: PCDH19 is emerging as a major gene for infantile-onset familial or sporadic epilepsy in female patients with or without mental retardation. In our cohort, epileptic encephalopathy with DS-like features and focal epilepsy of variable severity were the associated phenotypes and were equally represented. Copyright © 2010 by AAN Enterprises, Inc. All rights reserved.
PubMed | University of Trieste, C Besta National Neurological Institute Foundation, Child Neurology and Psychiatry Unit and C Mondino National Neurological Institute
Type: | Journal: Human genome variation | Year: 2016
The SPRED1 gene encodes a protein involved in the Ras/MAPK (mitogen-activated protein kinase) signaling pathway. Mutations in SPRED1 have been reported to cause Legius Syndrome, a rare developmental disorder that shares some clinical features with Neurofibromatosis-1. Direct sequencing was used to define SPRED1 mutations. We present two previously undescribed mutations: a frameshift mutation causing a stop codon, which was identified in an Italian family (p.Ile60Tyrfs*18) and a missense variation, which was identified in one sporadic Italian case (p.Pro422Arg). Our results led us to hypothesize that these modifications may contribute to the Legius Syndrome phenotype. Further studies will be needed to determine the roles of these mutations in the mechanisms of Legius Syndrome.
PubMed | University of Edinburgh, Child Neurology and Psychiatry Unit, C Mondino National Neurological Institute and University of Milan
Type: Journal Article | Journal: Human molecular genetics | Year: 2015
Aicardi-Goutires syndrome (AGS) is an inflammatory encephalopathy caused by defective nucleic acids metabolism. Over 50% of AGS mutations affect RNase H2 the only enzyme able to remove single ribonucleotide-monophosphates (rNMPs) embedded in DNA. Ribonucleotide triphosphates (rNTPs) are incorporated into genomic DNA with relatively high frequency during normal replication making DNA more susceptible to strand breakage and mutations. Here we demonstrate that human cells depleted of RNase H2 show impaired cell cycle progression associated with chronic activation of post-replication repair (PRR) and genome instability. We identify a similar phenotype in cells derived from AGS patients, which indeed accumulate rNMPs in genomic DNA and exhibit markers of constitutive PRR and checkpoint activation. Our data indicate that in human cells RNase H2 plays a crucial role in correcting rNMPs misincorporation, preventing DNA damage. Such protective function is compromised in AGS patients and may be linked to unscheduled immune responses. These findings may be relevant to shed further light on the mechanisms involved in AGS pathogenesis.
PubMed | University of Brescia, University of Pavia, Child Neurology and Psychiatry Unit and National Neurological Institute IRCCS C
Type: Journal Article | Journal: Molecular cytogenetics | Year: 2016
Partial deletion of chromosome 21q is a very rare chromosomal abnormality associated with highly variable phenotypes, such as facial dysmorphic features, heart defects, seizures, psychomotor delay, and severe to mild intellectual disability, depending on the location and size of deletions. So far, three broad deletion regions of 21q have been correlated with the clinical phenotype.We described the clinical and genetic features of three family members (father and two siblings) and other two unrelated patients with very wide range in age of diagnosis. All of them showed intellectual disability with very variable symptoms, from mild to severe, and carried 21q interstitial deletions with different sizes and position, as detected by conventional karyotype and array-CGH.Our study provided additional cases of partial 21q deletions, allowing to better delineate the genotype-phenotype correlations. In contrast to previous observations, we showed that deletions of the 21q proximal region are not necessarily associated with severe phenotypes and, therefore, that mild phenotypes are not exclusively related to distal deletions. To the best of our knowledge, this is the first report showing 21q deletions in adult patients associated with mild phenotypes, mainly consisting of neurobehavioral abnormalities, such as obsessive-compulsive disorders, poor social interactions and vulnerability to psychosis.