Medical Genetic Unit

San Giovanni Rotondo, Italy

Medical Genetic Unit

San Giovanni Rotondo, Italy
Time filter
Source Type

Micale L.,IRCCS Casa Sollievo Della Sofferenza Hospital | Augello B.,IRCCS Casa Sollievo Della Sofferenza Hospital | Maffeo C.,IRCCS Casa Sollievo Della Sofferenza Hospital | Selicorni A.,University of Milan Bicocca | And 37 more authors.
Human Mutation | Year: 2014

Kabuki syndrome (KS) is a multiple congenital anomalies syndrome characterized by characteristic facial features and varying degrees of mental retardation, caused by mutations in KMT2D/MLL2 and KDM6A/UTX genes. In this study, we performed a mutational screening on 303 Kabuki patients by direct sequencing, MLPA, and quantitative PCR identifying 133 KMT2D, 62 never described before, and four KDM6A mutations, three of them are novel. We found that a number of KMT2D truncating mutations result in mRNA degradation through the nonsense-mediated mRNA decay, contributing to protein haploinsufficiency. Furthermore, we demonstrated that the reduction of KMT2D protein level in patients' lymphoblastoid and skin fibroblast cell lines carrying KMT2D-truncating mutations affects the expression levels of known KMT2D target genes. Finally, we hypothesized that the KS patients may benefit from a readthrough therapy to restore physiological levels of KMT2D and KDM6A proteins. To assess this, we performed a proof-of-principle study on 14 KMT2D and two KDM6A nonsense mutations using specific compounds that mediate translational readthrough and thereby stimulate the re-expression of full-length functional proteins. Our experimental data showed that both KMT2D and KDM6A nonsense mutations displayed high levels of readthrough in response to gentamicin treatment, paving the way to further studies aimed at eventually treating some Kabuki patients with readthrough inducers. In this report, we have expanded the spectrum of mutations of KMT2D and KDM6A genes by analysing our cohort of 303 Kabuki patients by direct sequencing, MLPA and quantitative PCR. Based on KMT2D biological role, we designed functional studies that highlighted the haploinsufficiency of KMT2D as one of the mechanisms underlying the pathogenesis of the disease. Moreover, we provided the first preliminary proof-of-concept that occurring nonsense mutations in KMT2D and KDM6A can be effectively suppressed and the functional endogenous protein level and biological activity of KMT2D and KDM6A proteins restored. © 2014 The Authors.

Paciorkowski A.R.,Washington University in St. Louis | Thio L.L.,Washington University in St. Louis | Thio L.L.,St Louis Childrens Hospital | Rosenfeld J.A.,Signature | And 19 more authors.
European Journal of Human Genetics | Year: 2011

Infantile spasms (ISS) are an epilepsy disorder frequently associated with severe developmental outcome and have diverse genetic etiologies. We ascertained 11 subjects with ISS and novel copy number variants (CNVs) and combined these with a new cohort with deletion 1p36 and ISS, and additional published patients with ISS and other chromosomal abnormalities. Using bioinformatics tools, we analyzed the gene content of these CNVs for enrichment in pathways of pathogenesis. Several important findings emerged. First, the gene content was enriched for the gene regulatory network involved in ventral forebrain development. Second, genes in pathways of synaptic function were overrepresented, significantly those involved in synaptic vesicle transport. Evidence also suggested roles for GABAergic synapses and the postsynaptic density. Third, we confirm the association of ISS with duplication of 14q12 and maternally inherited duplication of 15q11q13, and report the association with duplication of 21q21. We also present a patient with ISS and deletion 7q11.3 not involving MAGI2. Finally, we provide evidence that ISS in deletion 1p36 may be associated with deletion of KLHL17 and expand the epilepsy phenotype in that syndrome to include early infantile epileptic encephalopathy. Several of the identified pathways share functional links, and abnormalities of forebrain synaptic growth and function may form a common biologic mechanism underlying both ISS and autism. This study demonstrates a novel approach to the study of gene content in subjects with ISS and copy number variation, and contributes further evidence to support specific pathways of pathogenesis. © 2011 Macmillan Publishers Limited All rights reserved.

Bacci C.,University of Florence | Sestini R.,University of Florence | Ammannati F.,Careggi Hospital | Bianchini E.,Pathology Unit | And 5 more authors.
Clinical Genetics | Year: 2010

Ganglioneuroma is a rare benign tumor originating from autonomic ganglia and is considered the benign counterpart of neuroblastoma. Ganglioneuromas may be present as an isolated finding and, rarely, in association with neurofibromatosis type 1 (NF1). However, ganglioneuromas of the cervical spine with intradural extension and multiple locations are extremely rare. We describe a 32-year-old woman with multiple ganglioneuromas of the cervical, dorsal and lumbar spine associated with a few café-au-lait spots and subcutaneous nodules. The patient lacked other NF1 stigmata, such as freckling, Lisch nodules and cutaneous neurofibromas. Although our patient did not fulfill the NF1 diagnostic criteria, molecular diagnosis revealed a pathogenic mutation in the NF1 gene. Approximately 30 patients affected by NF1 and ganglioneuromas have been reported: in all these individuals, NF1 diagnosis was made according to the clinical diagnostic criteria and no patients have molecular diagnosis. Therefore, this is the first case with multiple spinal ganglioneuromas associated with a pathogenic NF1 mutation. © 2009 John Wiley & Sons A/S.

PubMed | Bambino Gesu Childrens Research Hospital, Medical Genetic Unit, University of Florence, Meyer Children Hospital and Careggi General Hospital and A Meyer Childrens Hospital
Type: Case Reports | Journal: Journal of medical genetics | Year: 2015

Loss-of-function mutations of the FLNA gene cause a neuronal migration disorder defined as X-linked periventricular nodular heterotopia (PNH); gain-of-function mutations are associated with a group of X-linked skeletal dysplasias designed as otopalatodigital (OPD) spectrum. We describe a family in which a woman and her three daughters exhibited a complex phenotype combining PNH, epilepsy and Melnick-Needles syndrome (MNS), a skeletal disorder assigned to the OPD spectrum. All four individuals harboured a novel non-conservative missense mutation in FLNA exon 3.In all affected family members, we performed mutation analysis of the FLNA gene, RT-PCR, ultradeep sequencing analysis in FLNA cDNAs and western blot in lymphocyte cells to further characterise the mutation. We also assessed the effects on RT-PCR products of treatment of patients lymphocytes with cycloheximide, a nonsense mediated mRNA decay (NMD) inhibitor.We identified a novel c.622G>C change in FLNA exon 3, leading to the substitution of a highly conserved aminoacid (p.Gly208Arg). Gel electrophoresis and ultradeep sequencing revealed the missense mutation as well as retention of intron 3. Cycloheximide treatment demonstrated that the aberrant mRNA transcript-retaining intron 3 is subjected to NMD. Western blot analysis confirmed reduced FLNA levels in lymphocyte cells.The novel c.622G>C substitution leads to two aberrant FLNA transcripts, one of which carries the missense mutation, plus a longer transcript resulting from intron 3 retention. We propose that the exceptional co-occurrence of PNH and MNS, two otherwise mutually exclusive allelic phenotypes, is the consequence of a single mutational event resulting in co-occurring gain-of-function and loss-of-function effects.

PubMed | Scientific Committee of the Italian Moebius Syndrome Association, Medical Genetic Unit and University of Milan
Type: Journal Article | Journal: Italian journal of pediatrics | Year: 2016

Moebius syndrome (MBS) is rare disease characterized by nonprogressive congenital uni- or bi-lateral facial (i. e. VII cranial nerve) and abducens (i. e. VI cranial nerve) palsy. Although the neurological and ophthalmological findings are quite well-known, data concerning the attendant functional difficulties and their changes over time are seldom addressed. In this study we attempt to estimate the prevalence of clinical and functional data in an Italian cohort affected by MBS.The study included 50 children, 21 males and 29 females, aged 1month to 14years. The patients entered into a multidisciplinary diagnostic and follow-up protocol that had the specific purpose of detecting clinical and developmental deficits related to MBS.Involvement of the VII cranial nerve (total/partial, bilateral or unilateral) was present in 96% of patients, and of the VI nerve in 85%. Two patients were without impairment of the VII nerve and seven patients had no involvement of the VI nerve and were thus classified as Moebius-like because of the involvement of other CNs. Additional affected CNs were numbers III-IV in 16%, V in 11%, VIII and X each in 8%, the XI in 6%, the IX, most often partially, in 22%, and the XII in 48% of cases. Their development was characterized by global delay at one year of age, motor, emotional and speech difficulties at two years of age, a trend toward normalization at three years of age but with weakness in hand-eye coordination, and achieving average results at five years of age. Overall 90% of children had a normal developmental quotient whereas only 10% manifested cognitive deficits.Early rehabilitation may enhance the recovery of normal function, particularly in vulnerable areas of development. It is possible that early intervention that integrates sensory and visual information with emotional difficulties can improve the prognosis of the child with MBS.

PubMed | University of Sassari, University of Florence, Careggi Hospital and Medical Genetic Unit
Type: Case Reports | Journal: Gene | Year: 2014

Neurofibromatosis type 1 (NF1) is a rare autosomal dominant disease with an estimated incidence of 1 in 3000/3500 live births. NF1 is caused by a mutation in a gene which encodes a protein known as neurofibromin. In up to 5% of cases, NF1 is associated with pheochromocytomas. RET proto-oncogene encodes a member of the receptor tyrosine kinase family involved in the normal development or the neoplastic growth of neural crest cell lineages. Germ-line RET mutations account for cases of Multiple Endocrine Neoplasia type 2 (MEN2), an autosomal dominant genetic syndrome where medullary thyroid carcinoma (MTC) is the major and more clinically severe feature, with nearly complete penetrance. C-cell hyperplasia (CCH) is described in MEN2 patients, and it has been implicated as the precursor of in situ MTC. Patients with RET mutations develop pheochromocytomas in 50% of cases. Rarely, patients with NF1 have been found to present, in addition to the NF1 clinical picture, other lesions, such as parathyroid hyperplasia/adenoma and/or medullary thyroid carcinoma. In spite of the presence of these MEN2 lesions, in none of these patients mutations of gene RET have been found so far. In this report, we describe the first case of a patient affected by a germ-line mutation in both NF1 and RET genes.

Latiano A.,IRCCS Casa Sollievo della Sofferenza | Palmieri O.,IRCCS Casa Sollievo della Sofferenza | Pastorelli L.,Gastroenterology and Gastrointestinal Endoscopy Unit | Pastorelli L.,University of Milan | And 14 more authors.
PLoS ONE | Year: 2013

Background: Recent evidence suggests that the IL-33/IL1RL1 axis plays a critical role in several autoimmune and inflammatory disorders; however, its mechanistic role in inflammatory bowel disease (IBD) has not been clearly defined. We investigated the contribution of IL-33 and IL1RL1 polymorphisms to IBD risk, and possible correlations with phenotype in an Italian cohort of adult and pediatric patients. Methods: We evaluated the association of six SNPs in IL-33 and IL1RL1 genes, in 805 Crohn's disease (CD), 816 ulcerative colitis (UC), and 752 controls, using Taqman. IL-33 and IL1RL1 mRNA expression was also analyzed. Results: Significant allele and genotype associations with IL-33 rs3939286 were found in CD (P = 0.004; P = 0.035) and UC patients (P = 0.002; P = 0.038). After stratifying the cohort for age at diagnosis, the differences remained significant only in the IBD adult-onset. Significant associations were also obtained in CD patients with two IL1RL1 polymorphisms (rs13015714 and rs2058660, P<0.015). By combining homo- and heterozygous carriers of the rs13015714 risk allele, differences were still significant for both CD adult- and pediatric-onset. Upon genotype-phenotype evaluation, an increased frequency of extensive colitis in adult UC (P = 0.019) and in steroid-responsive pediatric patients (P = 0.024) carrying the IL-33 rs3939286 risk genotype, was observed. mRNA expression of IL-33 and IL1RL1 in inflamed IBD biopsy samples was significantly increased. Conclusions: Common IL-33 and IL1RL1 polymorphisms contribute to the risk of IBD in an Italian cohort of adult and pediatric patients, with some influence on sub-phenotypes. © 2013 Latiano et al.

Bedeschi M.F.,Medical Genetic Unit | Colombo L.,University of Milan | Mari F.,University of Siena | Hofmann K.,Friedrich - Alexander - University, Erlangen - Nuremberg | And 5 more authors.
Molecular Syndromology | Year: 2011

Van den Ende-Gupta syndrome (VDEGS) is a congenital condition characterized by craniofacial and skeletal manifestations, specifically blepharophimosis, malar and maxillary hypoplasia, distinctive nose, arachnocamptodactyly, and long slender bones of the hands and feet. To date, only 24 patients have been described. It is generally thought that the syndrome is transmitted by an autosomal recessive mode of inheritance, although evidence for genetic heterogeneity has recently been presented. We report on a girl followed from birth up to 3 years of life with a set of peculiar minor anomalies, arachnocamptodactyly of hands and feet, characteristic of VDEGS in association with a 22q11.12 deletion. Recently, the VDEGS gene was mapped to the DiGeorge syndrome region on 22q11.2, and homozygous mutations in the SCARF2 gene were identified. We now report the first patient with VDEGS due to compound heterozygosity for the common 22q11.2 microdeletion and a hemizygous SCARF2 splice site mutation. Copyright © 2011 S. Karger AG, Basel.

Margari L.,University of Bari | Di Cosola M.L.,Medical Genetic Unit | Buttiglione M.,University of Bari | Pansini A.,Hospital Of Venere | And 6 more authors.
American Journal of Medical Genetics, Part A | Year: 2012

Genomic copy number imbalances are being increasingly identified as an important cause of intellectual disability (ID) and behavioral disturbances. This article reports the clinical features, and long term follow-up of a patient with neurodevelopmental, cognitive, and behavioral abnormalities associated with facial dysmorphism, CNS anomalies, and epilepsy. The karyotype was normal; array CGH testing revealed a de novo cryptic aberration with a terminal 8p23.2p23.3 deletion, and a concomitant 12p13.31p13.33 duplication, of 6.86Mb, and 8.49Mb, respectively. Our patient clinical features are compared to those of partial 8 monosomy and/or partial 12p trisomy cases reported in literature, in order to establish genotype-phenotype correlations. For some features, for example, electroencephalogram (EEG) abnormalities and epilepsy, both abnormalities seem to make a contribution, while most phenotypic traits have been assigned to 8p monosomy or to 12p trisomy, contributing to a tentative phenotype map for partial monosomy of the short arm of chromosome 8, and trisomy of the short arm of chromosome 12. © 2012 Wiley Periodicals, Inc.

Margari L.,University of Bari | Lamanna A.L.,University of Bari | Craig F.,University of Bari | Simone M.,University of Bari | And 2 more authors.
European Journal of Pediatrics | Year: 2014

Abnormalities of the sex chromosomes (47, XXY, 47 XYY, 45,X/46,XY mosaicism) are frequently associated with Autism Spectrum Disorders (ASD), but the male predisposition to these disorders has not been clearly explained. Previously, the role of the X chromosome was considered important in the ASD mainly because autistic symptoms were detected in genetic syndromes involving X chromosome (fragile X syndrome, Rett syndrome, Klinefelter syndrome). Instead, few studies have analyzed the possible role of the Y chromosome in the ASD. This study explores the role of the Y chromosome in ASD through a systematic literature review about the association between ASD and XYY syndrome and a description of two new cases with this association. The literature review considered studies published in peer-reviewed journals, included in the MEDLINE and PubMed databases, that examined the association between ASD and XYY syndrome. Few studies reported the occurrence of ASD in children with XYY karyotype and the majority of them did not reported a well-defined autism diagnostic category associated with an extra Y chromosome, but several clinical conditions that are generically described as language and social impairment. Conclusion: This study underlines the underestimated role of the Y chromosome in ASD, and we postulate that all the ASD associated with the XYY karyotype may presumably fall within mild degree of ASD as in our cases. © 2014 Springer-Verlag Berlin Heidelberg.

Loading Medical Genetic Unit collaborators
Loading Medical Genetic Unit collaborators