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ABSTRACT: Anterior pituitary aplasia (APA) is a very rare cause of congenital-onset multiple pituitary hormone deficiency (CO-MPHD). We report on molecular analysis and clinical follow-up of three previously reported cases of APA [Scommegna et al., 2004], who share a characteristic physical and neuropsychological profile. Mutation analysis of genes encoding transcription factors involved in pituitary development (PROP1, POUF1, HESX1, LHX3, and LHX4) did not demonstrate a any mutation. In order to identify the genetic cause underlying the phenotypes we performed an array-based comparative genomic hybridization (array-CGH), which showed a cryptic interstitial deletion of 9p (200 kb), including the TEK and MOBKL2B, in one patient. Although an apparently identical deletion was carried by the clinically normal father, we assumed that the patient's phenotype might be due to a recessive mutation in the other allele. However, sequence analysis of exons and splice junctions of these genes did not detect pathogenic or predisposing variants in the three patients. We suggest that the constellation of clinical signs in these patients constitutes a previously undescribed syndrome, whose genetic cause has yet to be identified. © 2012 Wiley Periodicals, Inc.
American Journal of Medical Genetics Part A 09/2012; 158A(11):2750-5. · 2.39 Impact Factor
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ABSTRACT: Pitt-Hopkins syndrome (PTHS) is an emerging condition characterized by severe intellectual disability (ID), typical facial gestalt, and additional features, such as breathing abnormalities. Because of the overlapping phenotype of severe ID with absent speech, epilepsy, microcephaly, large mouth, and constipation, differential diagnosis of PTHS with respect to Angelman, Rett, and Mowat-Wilson syndromes represents a relevant clinical issue, and many patients are currently undergoing genetic tests for different conditions that are assumed to fall within the PTHS clinical spectrum. During a search for TCF4 mutations in 78 patients with a suspected PTHS, haploinsufficiency of TCF4 was identified in 18. By evaluating clinical features of patients with a proven TCF4 mutation with those of patients without, we noticed that, in addition to the typical facial gestalt, the PTHS phenotype results from the various combination of the following characteristics: ID with severe speech impairment, normal growth parameters at birth, postnatal microcephaly, breathing abnormalities, motor incoordination, ocular anomalies, constipation, seizures, typical behavior, and subtle brain abnormalities. On the basis of these observations, here we propose a clinically based score system as useful tool for driving a first choice molecular test for PTHS. This scoring system is also proposed for a clinically based diagnosis of PTHS in absence of a proven TCF4 mutation.
American Journal of Medical Genetics Part A 06/2012; 158A(7):1604-11. · 2.39 Impact Factor
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ABSTRACT: Intellectual disability (ID) with autosomal recessive (AR) inheritance is believed to be common; however, very little is known about causative genes and genotype-phenotype correlations. The broad genetic heterogeneity of AR-ID, and its usually nonsyndromic nature make it difficult to pool multiple pedigrees with the same underlying genetic defect to achieve consistent nosology. Nearly all autosomal genes responsible for recessive cognitive disorders have been identified in large consanguineous families from the Middle East, and nonsense mutations in TRAPPC9 have been reported in a total of 5. Although several recurrent phenotypic abnormalities are described in some of these patients, the associated phenotype is usually referred to as nonsyndromic. By means of single-nucleotide polymorphism-array first and then by exome sequencing, we identified a new pathogenic mutation in TRAPPC9 in two Italian sisters born to healthy and apparently nonconsanguineous parents. It consists of a homozygous splice site mutation causing exon skipping with frameshift and premature termination, as confirmed by mRNA sequencing. By detailed phenotypic analysis of our patients, and by critical literature review, we found that homozygous TRAPPC9 loss-of-function mutations cause a distinctive phenotype, characterized by peculiar facial appearance, obesity, hypotonia (all signs resembling a Prader-Willi-like phenotype), moderate-to-severe ID, and consistent brain abnormalities.European Journal of Human Genetics advance online publication, 2 May 2012; doi:10.1038/ejhg.2012.79.
European journal of human genetics: EJHG 05/2012; · 3.56 Impact Factor
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ABSTRACT: The chromosome 17q21.31 deletion syndrome is a genomic disorder characterized by highly distinctive facial features, moderate-to-severe intellectual disability, hypotonia and friendly behavior. Here, we show that de novo loss-of-function mutations in KANSL1 (also called KIAA1267) cause a full del(17q21.31) phenotype in two unrelated individuals that lack deletion at 17q21.31. These findings indicate that 17q21.31 deletion syndrome is a monogenic disorder caused by haploinsufficiency of KANSL1.
Nature Genetics 04/2012; 44(6):636-8. · 35.53 Impact Factor
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ABSTRACT: We report on a patient with a 1.2 Mb 19p13.12-p13.13 deletion. Compared to previously reported individuals with partially overlapping deletions, the propositus presented with a less severe phenotype, consisting of mild intellectual disability and behavior anomalies, with episodes of simple febrile seizures and without significant physical anomalies or major malformations. The deleted region includes 29 coding genes, some of which have already been demonstrated to be involved in cognitive processes. Mutations in two of them, CC2D1A and TECR, were recently reported to be responsible for non-syndromal, autosomal recessive intellectual disability. The residual alleles of all of these genes were submitted to sequence analysis. No sequence variants were found that could be considered pathogenic. This patient constitutes a further example of the wide phenotypic variability associated with chromosomal rearrangements, likely due to the different size of deleted/duplicated segments.
American Journal of Medical Genetics Part A 03/2012; 158A(4):888-93. · 2.39 Impact Factor
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Giuseppe Marangi,
Stefania Ricciardi, Daniela Orteschi,
Serena Lattante,
Marina Murdolo,
Bruno Dallapiccola,
Chiara Biscione,
Rosetta Lecce,
Pietro Chiurazzi,
Corrado Romano, [......],
Cinzia Magnani,
Paolo Bonanni,
Federica Martinez,
Gigliola Serra,
Domenica Battaglia,
Donatella Lettori,
Gessica Vasco,
Anna Baroncini,
Cecilia Daolio,
Marcella Zollino
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ABSTRACT: Pitt-Hopkins syndrome (PTHS) is characterized by severe intellectual disability, typical facial gestalt and additional features, such as breathing anomalies. Following the discovery of the causative haploinsufficiency of transcription factor 4 (TCF4), about 60 patients have been reported. We looked for TCF4 mutations in 63 patients with a suspected PTHS. Haploinsufficiency of TCF4 was identified in 14 patients, as a consequence of large 18q21.2 chromosome deletions involving TCF4 (2 patients), gene mutations (11 patients) and a t(14q;18q) balanced translocation disrupting TCF4 (one patient). By evaluating the clinical features of these patients, along with literature data, we noticed that, in addition to the typical facial gestalt, the PTHS phenotype results from the various combinations of the following characteristics: intellectual disability with severe speech impairment, normal growth parameters at birth, postnatal microcephaly, breathing anomalies, motor incoordination, ocular anomalies, constipation, seizures, typical behavior and subtle brain abnormalities. Although PTHS is currently considered to be involved in differential diagnosis with Angelman and Rett syndromes, we found that combining the facial characteristics with a detailed analysis of both the physical and the neurological phenotype, made molecular testing for PTHS the first choice. Based on striking clinical criteria, a diagnosis of PTHS was made clinically in two patients who had normal TCF4. This report deals with the first series of PTHS patients of Italian origin.
American Journal of Medical Genetics Part A 07/2011; 155A(7):1536-45. · 2.39 Impact Factor
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Giuseppe Marangi,
Stefania Ricciardi, Daniela Orteschi,
Serena Lattante,
Marina Murdolo,
Bruno Dallapiccola,
Chiara Biscione,
Rosetta Lecce,
Pietro Chiurazzi,
Corrado Romano, [......],
Cinzia Magnani,
Paolo Bonanni,
Federica Martinez,
Gigliola Serra,
Domenica Battaglia,
Donatella Lettori,
Gessica Vasco,
Anna Baroncini,
Cecilia Daolio,
Marcella Zollino
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ABSTRACT: Pitt-Hopkins syndrome (PTHS) is characterized by severe intellectual disability, typical facial gestalt and additional features, such as breathing anomalies. Following the discovery of the causative haploinsufficiency of transcription factor 4 (TCF4), about 60 patients have been reported. We looked for TCF4 mutations in 63 patients with a suspected PTHS. Haploinsufficiency of TCF4 was identified in 14 patients, as a consequence of large 18q21.2 chromosome deletions involving TCF4 (2 patients), gene mutations (11 patients) and a t(14q;18q) balanced translocation disrupting TCF4 (one patient). By evaluating the clinical features of these patients, along with literature data, we noticed that, in addition to the typical facial gestalt, the PTHS phenotype results from the various combinations of the following characteristics: intellectual disability with severe speech impairment, normal growth parameters at birth, postnatal microcephaly, breathing anomalies, motor incoordination, ocular anomalies, constipation, seizures, typical behavior and subtle brain abnormalities. Although PTHS is currently considered to be involved in differential diagnosis with Angelman and Rett syndromes, we found that combining the facial characteristics with a detailed analysis of both the physical and the neurological phenotype, made molecular testing for PTHS the first choice. Based on striking clinical criteria, a diagnosis of PTHS was made clinically in two patients who had normal TCF4. This report deals with the first series of PTHS patients of Italian origin. © 2011 Wiley-Liss, Inc.
American Journal of Medical Genetics Part A 06/2011; 155(7):1536 - 1545. · 2.39 Impact Factor
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ABSTRACT: A de novo 0.3 Mb deletion on 6p21.3 was detected by array-comparative genomic hybridization in a girl with mental retardation, drug-resistant seizures, facial dysmorphisms, gut malrotation and abnormal pancreas segmentation. Consistent with phenotypic manifestations is haploinsufficiency of SYNGAP1, which was recently demonstrated to cause non-syndromic mental retardation, and of the flanking genes CuTA, a likely modulator of the processing and trafficking of secretory proteins in the human brain, and hPHF1, involved in HOX gene silencing. Mutations of both CuTA and hPHF1 were never reported as causative of human diseases. Similarly, the present syndromic condition was not previously described and it can be regarded as a human model confirming the suggested biological properties of the genes included in the deletion interval. In addition, experimental evidence that SYNGAP1 and CuTA are involved in the secretory pathway in neurons, through glutamate and acetylcholinesterase signalling, prompted us to consider modulation of the glutamate pathway as target of a therapeutic strategy for seizure control.
European journal of human genetics: EJHG 02/2011; 19(2):239-42. · 3.56 Impact Factor
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Simona Giovannini,
Daniele Frattini,
Angela Scarano,
Carlo Fusco,
Gianna Bertani,
Elvio Della Giustina,
Paola Martinelli, Daniela Orteschi,
Marcella Zollino,
Giovanni Neri,
Giuseppe Gobbi
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ABSTRACT: Epilepsy is the most common and serious neurological symptom in ring chromosome 14 syndrome, also characterised by mild dysmorphisms, acquired microcephaly, cognitive impairment, hypotonia and ocular abnormalities. Typically, early-onset, polymorphous and drug-resistant seizures are reported. Status epilepticus has not been previously reported. We describe a nine-year-old Caucasian boy with ring 14 syndrome who presented a severe early-onset and drug-resistant focal epilepsy with secondary generalised seizures and repetitive episodes of convulsive and non-convulsive status epilepticus. The electro-clinical evaluation of prolonged seizures and their long-term consequences is important for the practical management of these patients and for a better comprehension of the syndrome.
Epileptic disorders: international epilepsy journal with videotape 09/2010; 12(3):222-7. · 1.50 Impact Factor
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American Journal of Medical Genetics Part A 01/2010; 152A(1):237. · 2.39 Impact Factor
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American Journal of Medical Genetics Part A 12/2009; 152A(1):258-61. · 2.39 Impact Factor
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ABSTRACT: BACKGROUND Beckwith-Wiedemann syndrome (BWS) is a clinically variable and genetically heterogeneous disorder, providing evidence that imprinted genes play key roles in the control of fetal growth. Clinically, diagnostic criteria include macrosomia, macroglossia, abdominal wall defects, neonatal hypoglycaemia, visceromegalies and hemihyperplasia. Component clinical manifestations also include renal abnormalities, adrenocortical cytomegaly and a characteristic facial appearance, with midface hypoplasia and ear anomalies. Genetically, BWS is associated with disturbances within two different domains on 11p15 that are controlled by distinct imprinting control regions (ICR), ICR1 and ICR2. The majority of patients have abnormalities within ICR2. In particular, loss of maternal methylation accounts for 50-60% of cases, and is associated with reduction in the expression of the CDKN1C gene, a member of the cyclin dependent kinase inhibitor family acting as negative regulator of cell proliferation. Mutations in CDKN1C are detected in another 5-10% of subjects with sporadic BWS. Chromosome deletions affecting ICR2 are uncommon. METHODS AND FINDINGS We report on a patient with BWS in which a de novo 11p15 deletion was detected by array comparative genomic hybridisation. Clinically, the patient presented with mild mental retardation and minor physical anomalies. The deletion, that was demonstrated to be maternal in origin by SNP array, encompassed ICR2 and several flanking genes, including CDKN1C. A normal methylation pattern of ICR1 was observed. CONCLUSIONS This observation provides evidence that, among the genetic defects associated with BWS, a 11p15 microdeletion encompassing ICR2 identifies a peculiar clinical phenotype, with high recurrence risk in offspring of female carriers. It also supports the model of two independent domains within the BWS locus.
Journal of Medical Genetics 10/2009; 47(6):429-32. · 6.36 Impact Factor
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Mario Sabatelli,
Fabrizio Eusebi,
Ammar Al-Chalabi,
Amelia Conte,
Francesca Madia,
Marco Luigetti,
Irene Mancuso,
Cristina Limatola,
Flavia Trettel,
Fabrizia Sobrero, [......],
Claudia Moriconi,
Sergio Fucile,
Serena Lattante,
Giuseppe Marangi,
Marina Murdolo, Daniela Orteschi,
Alessandra Del Grande,
Pietro Tonali,
Giovanni Neri,
Marcella Zollino
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ABSTRACT: Sporadic amyotrophic lateral sclerosis (SALS) is a motor neuron degenerative disease of unknown etiology. Current thinking on SALS is that multiple genetic and environmental factors contribute to disease liability. Since neuronal acetylcholine receptors (nAChRs) are part of the glutamatergic pathway, we searched for sequence variants in CHRNA3, CHRNA4 and CHRNB4 genes, encoding neuronal nicotinic AChR subunits, in 245 SALS patients and in 450 controls. We characterized missense variants by in vitro mutagenesis, cell transfection and electrophysiology. Sequencing the regions encoding the intracellular loop of AChRs subunits disclosed 15 missense variants (6.1%) in 14 patients compared with only six variants (1.3%) in controls (P = 0.001; OR 4.48, 95% CI 1.7-11.8). The frequency of variants in exons encoding extracellular and transmembrane domains and in intronic regions did not differ. NAChRs formed by mutant alpha3 and alpha4 and wild-type (WT) beta4 subunits exhibited altered affinity for nicotine (Nic), reduced use-dependent rundown of Nic-activated currents (I(Nic)) and reduced desensitization leading to sustained intracellular Ca(2+) concentration, in comparison with WT-nAChR. The cellular loop has a crucial importance for receptor trafficking and regulating ion channel properties. Missense variants in this domain are significantly over-represented in SALS patients and alter functional properties of nAChR in vitro, resulting in increased Ca(2+) entry into the cells. We suggest that these gain-of-function variants might contribute to disease liability in a subset of SALS because Ca(2+) signals mediate nAChR's neuromodulatory effects, including regulation of glutamate release and control of cell survival.
Human Molecular Genetics 08/2009; 18(20):3997-4006. · 7.64 Impact Factor
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ABSTRACT: The ring 14 (r14) syndrome is a rare condition, whose precise clinical and genetic characterization is still lacking. We analyzed a total of 20 patients with r14 and another 9 patients with a linear 14q deletion. The ring was complete, with no apparent loss of chromosome material, in 6 cases; a terminal 14q deletion, varying in size from 0.65 to 5 Mb, was detected in the remaining 14 cases. Deleted ring chromosomes were 70% paternal and 30% maternal. UPD (14) was never detected. With respect to the linear 14q deletions, three were proximal, varying in size from 4 to 7.2 Mb, and six distal, varying in size from 4.8 to 20 Mb. The majority of the linear deletions were also of paternal origin, and UPD (14) was excluded in all cases. Clinically, the r14 syndrome was characterized by a recognizable phenotype, consisting of shortness of stature, a distinctive facial appearance, microcephaly, scoliosis, and ocular abnormalities, which included abnormal retinal pigmentation, strabismus, glaucoma, and abnormal macula. All patients except one had mental retardation. Drug-resistant epilepsy was another highly consistent finding. Aggressive and hyperactive behavior was noted in about half of the patients. Based on genotype-phenotype correlations, we could deduce that retinal abnormalities, epilepsy, microcephaly, and mental retardation map within the proximal 14q11.2-q12 region. Likewise, behavior disorders and scoliosis could be assigned to the 14q32 region.
American Journal of Medical Genetics Part A 06/2009; 149A(6):1116-24. · 2.39 Impact Factor
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ABSTRACT: The authors report the study of a 30-month-old girl with refractory myoclonic epilepsy associated with mental retardation, growth delay, peculiar facial appearance, and minor physical anomalies. Extensive genetic studies were performed, including an array-based comparative genomic hybridization (array-CGH) that showed a cryptic interstitial deletion of 15q (5 Mb) affecting the 15q26.1-26.2 region. Partial deletions of the long arm of chromosome 15, including the 15q26 region, were observed in syndromic associations that typically include congenital diaphragmatic hernia, but neurologic features were poorly described and epileptic seizures were never reported. Our findings suggest that genes for seizures could be included in the 15q26.1q26.2 deletion interval.
Epilepsia 05/2009; 50(7):1810-5. · 3.96 Impact Factor
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Alessandra Terracciano,
Carlo Casali,
Gaetano S Grieco, Daniela Orteschi,
Silvia Di Giandomenico,
Laura Seminara,
Roberto Di Fabio,
Rosalba Carrozzo,
Alessandro Simonati,
Giovanni Stevanin,
Marcella Zollino,
Filippo M Santorelli
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ABSTRACT: Autosomal recessive spastic ataxia of Charlevoix-Saguenay is a neurodegenerative disorder characterized by early-onset, spastic ataxia and peripheral neuropathy, with or without mental retardation. The array of mutations in SACS has expanded worldwide after the first description in Quebec. We herein report the identification of an unconventional SACS mutation, a large-scale deletion sized approximately 1.5 Mb encompassing the whole gene, in two unrelated patients. The clinical phenotype of the patients was similar to more canonical ARSACS cases, though it is was complicated by the unusual presence of hearing loss. Our findings suggest that a "microdeletion" on chromosome 13q12 represents a novel allelic variant associated with ARSACS, stressing the need for an expanded testing in molecular diagnostic laboratories.
Neurogenetics 12/2008; 10(2):151-5. · 3.35 Impact Factor
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ABSTRACT: We report on a 16-year-old girl with a multiple congenital anomalies/mental retardation condition, in which a 1.7 Mb tandem duplication of chromosome region 16p13.3 was detected by array-CGH. Mental retardation was moderate (IQ 45), with very limited speech. She had tall stature with relative microcephaly. Clinical manifestations included distinctive facial appearance with deep set eyes, narrow palpebral fissures, wide nasal bridge, long philtrum, rounded nasal tip, thin upper lip, protruding mandible and abnormal auricles, hand and foot anomalies. The causal 16p13.3 duplication is one of the smallest reported so far, and includes the CBP gene, whose haploinsufficiency is responsible for the Rubinstein-Taybi syndrome. By comparing clinical manifestations of our patient with those of patients carrying similar rearrangements, we could infer that 16p13.3 microduplications encompassing the Rubinstein-Taybi region result in a recognizable clinical condition, most likely representing a single gene disorder.
American Journal of Medical Genetics Part A 10/2008; 146A(18):2313-7. · 2.39 Impact Factor
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Marcella Zollino,
Rosetta Lecce,
Marina Murdolo, Daniela Orteschi,
Giuseppe Marangi,
Angelo Selicorni,
Alina Midro,
Giovanni Sorge,
Giuseppe Zampino,
Luigi Memo, [......],
Yolanda Gyftodimou,
Francesca Faravelli,
Romano Tenconi,
Livia Garavelli,
Laura Mazzanti,
Rita Fischetto,
Pietro Cavalli,
Salvatore Savasta,
Laura Rodriguez,
Giovanni Neri
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ABSTRACT: The basic genomic defect in Wolf-Hirschhorn syndrome (WHS), including isolated 4p deletions and various unbalanced de novo 4p;autosomal translocations and above all t(4p;8p), is heterogeneous. Olfactory receptor gene clusters (ORs) on 4p were demonstrated to mediate a group of WHS-associated t(4p;8p)dn translocations. The breakpoint of a 4-Mb isolated deletion was also recently reported to fall within the most distal OR. However, it is still unknown whether ORs mediate all 4p-autosomal translocations, or whether they are involved in the origin of isolated 4p deletions. Another unanswered question is whether a parental inversion polymorphism on 4p16 can act as predisposing factor in the origin of WHS-associated rearrangements. We investigated the involvement of the ORs in the origin of 73 WHS-associated rearrangements. No hotspots for rearrangements were detected. Breakpoints on 4p occurred within the proximal or the distal olfactory receptor gene cluster in 8 of 73 rearrangements (11%). These were five t(4p;8p) translocations, one t(4p;7p) translocation and two isolated terminal deletions. ORs were not involved in one additional t(4p;8p) translocation, in a total of nine different 4p;autosomal translocations and in the majority of isolated deletions. The presence of a parental inversion polymorphism on 4p was investigated in 30 families in which the 4p rearrangements, all de novo, were tested for parental origin (7 were maternal and 23 paternal). It was detected only in the mothers of 3 t(4p;8p) cases. We conclude that WHS-associated chromosome changes are not usually mediated by low copy repeats. The 4p16.3 inversion polymorphism is not a risk factor for their origin.
Human Genetics 01/2008; 122(5):423-30. · 5.07 Impact Factor
