Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Smith-Magenis Syndrome-Clinical Review, Biological Background and Related Disorders.

ABSTRACT: Smith-Magenis syndrome (SMS) is a complex genetic disorder characterized by distinctive physical features, developmental delay, cognitive impairment, and a typical behavioral phenotype. SMS is caused by interstitial 17p11.2 deletions (90%), encompassing multiple genes and including the retinoic acid-induced 1 gene (RAI1), or by pathogenic variants in RAI1 itself (10%). RAI1 is a dosage-sensitive gene expressed in many tissues and acting as transcriptional regulator. The majority of individuals exhibit a mild-to-moderate range of intellectual disability. The behavioral phenotype includes significant sleep disturbance, stereotypes, maladaptive and self-injurious behaviors. In this review, we summarize current clinical knowledge and therapeutic approaches. We further discuss the common biological background shared with other conditions commonly retained in differential diagnosis.

SUBMITTER: Rinaldi B

PROVIDER: S-EPMC8872351 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Smith-Magenis Syndrome-Clinical Review, Biological Background and Related Disorders.

Rinaldi Berardo B Villa Roberta R Sironi Alessandra A Garavelli Livia L Finelli Palma P Bedeschi Maria Francesca MF

Genes 20220211 2

Smith-Magenis syndrome (SMS) is a complex genetic disorder characterized by distinctive physical features, developmental delay, cognitive impairment, and a typical behavioral phenotype. SMS is caused by interstitial 17p11.2 deletions (90%), encompassing multiple genes and including the retinoic acid-induced 1 gene (RAI1), or by pathogenic variants in RAI1 itself (10%). RAI1 is a dosage-sensitive gene expressed in many tissues and acting as transcriptional regulator. The majo ...[more]

PMID: 35205380

Similar Datasets

Autism spectrum features in Smith-Magenis syndrome.

Project description:Smith-Magenis syndrome (SMS; OMIM 182290) is a neurodevelopmental disorder characterized by a well-defined pattern of anomalies. The majority of cases are due to a common deletion in chromosome 17p11.2 that includes the RAI1 gene. In children with SMS, autistic-like behaviors and symptoms start to emerge around 18 months of age. This study included 26 individuals (15 females and 11 males), with a confirmed deletion (del 17p11.2). Parents/caregivers were asked to complete the Social Responsiveness Scale (SRS) and the Social Communication Questionnaire (SCQ) both current and lifetime versions. The results suggest that 90% of the sample had SRS scores consistent with autism spectrum disorders. Moreover, females showed more impairment in total T-scores (P?=?0.02), in the social cognition (P?=?0.01) and autistic mannerisms (P?=?0.002) subscales. The SCQ scores are consistent to show that a majority of individuals may meet criteria for autism spectrum disorders at some point in their lifetime. These results suggest that SMS needs to be considered in the differential diagnosis of autism spectrum disorders but also that therapeutic interventions for autism are likely to benefit individuals with SMS. The mechanisms by which the deletion of RAI1 and contiguous genes cause psychopathology remain unknown but they provide a solid starting point for further studies of gene-brain-behavior interactions in SMS and autism spectrum disorders.

| S-EPMC2967410 | biostudies-literature

RAI1 gene mutations: mechanisms of Smith-Magenis syndrome.

Project description:Smith-Magenis syndrome (SMS; OMIM #182290) is a complex genetic disorder characterized by distinctive physical features, developmental delay, cognitive impairment, and a typical behavioral phenotype. SMS is caused by interstitial 17p11.2 deletions, encompassing multiple genes and including the retinoic acid-induced 1 gene (RAI1), or by mutations in RAI1 itself. About 10% of all the SMS patients, in fact, carry an RAI1 mutation responsible for the phenotype. RAI1 (OMIM *607642) is a dosage-sensitive gene expressed in many tissues and highly conserved among species. Over the years, several studies have demonstrated that RAI1 (or its homologs in animal models) acts as a transcriptional factor implicated in embryonic neurodevelopment, neuronal differentiation, cell growth and cell cycle regulation, bone and skeletal development, lipid and glucose metabolisms, behavioral functions, and circadian activity. Patients with RAI1 pathogenic variants show some phenotypic differences when compared to those carrying the typical deletion. They usually have lower incidence of hypotonia and less cognitive impairment than those with 17p11.2 deletions but more frequently show the behavioral characteristics of the syndrome and overeating issues. These differences reflect the primary pathogenetic role of RAI1 without the pathogenetic contribution of the other genes included in the typical 17p11.2 deletion. The better comprehension of physiological roles of RAI1, its molecular co-workers and interactors, and its contribution in determining the typical SMS phenotype will certainly open a new path for therapeutic interventions.

| S-EPMC5680963 | biostudies-literature

Behavior and sleep disturbance in Smith-Magenis syndrome.

Project description:PURPOSE OF REVIEW:To provide an update of the most recent studies on Smith-Magenis syndrome (SMS) with a focus on the unique pattern of behavioral and sleep disturbances associated with the condition. RECENT FINDINGS:The recent literature on SMS has focused on the characteristic severe behavioral and sleep disturbances. A better understanding of the underlying pathophysiological mechanisms and common clinical course has helped further characterize SMS, while much is left to be discovered in regard to effective treatment/management. SUMMARY:SMS is a difficult to manage genetic condition defined by pervasive and progressive behavioral and sleep disturbances with a unique pattern that can often be easily discerned from other neurodevelopmental disorders. Common behavioral features include maladaptive/self-injurious, aggressive, stereotypic, and the newly appreciated food seeking behaviors associated with SMS. In addition, there is a sleep disturbance defined by an altered circadian rhythm with frequent nighttime waking and daytime sleepiness, causing patients and families significant distress. Small studies have suggested some treatment/management approaches to the behavioral and sleep disturbances, however, much remains to be discovered.

| S-EPMC6362978 | biostudies-literature

Behavioral disturbance and treatment strategies in Smith-Magenis syndrome.

Project description:BackgroundSmith-Magenis syndrome is a complex neurodevelopmental disorder that includes intellectual deficiency, speech delay, behavioral disturbance and typical sleep disorders. Ninety percent of the cases are due to a 17p11.2 deletion encompassing the RAI1 gene; other cases are linked to mutations of the same gene. Behavioral disorders often include outbursts, attention deficit/hyperactivity disorders, self-injury with onychotillomania and polyembolokoilamania (insertion of objects into body orifices), etc. Interestingly, the stronger the speech delay and sleep disorders, the more severe the behavioral issues. Sleep disturbances associate excessive daytime sleepiness with nighttime agitation. They are underpinned by an inversion of the melatonin secretion cycle. However, the combined intake of beta-blockers in the morning and melatonin in the evening may radically alleviate the circadian rhythm problems.DiscussionOnce sleep disorders are treated, the next challenge is finding an effective treatment for the remaining behavioral problems. Unfortunately, there is a lack of objective guidelines. A comprehensive evaluation of such disorders should include sleep disorders, potential causes of pain, neurocognitive level and environment (i.e. family and school). In any case, efforts should focus on improving communication skills, identifying and treating attention deficit/hyperactivity, aggressiveness and anxiety. Treatment of Smith-Magenis syndrome is complex and requires a multidisciplinary team including, among others, geneticists, psychiatrists, neuropediatricians/neurologists, somnologists, developmental and behavioral pediatricians, and speech and language therapists.

| S-EPMC4559928 | biostudies-literature

Frameshift mutation hotspot identified in Smith-Magenis syndrome: case report and review of literature.

Project description:Smith-Magenis syndrome (SMS) is a complex syndrome involving intellectual disabilities, sleep disturbance, behavioural problems, and a variety of craniofacial, skeletal, and visceral anomalies. While the majority of SMS cases harbor an ~3.5 Mb common deletion on 17p11.2 that encompasses the retinoic acid induced-1 (RAI1) gene, some patients carry small intragenic deletions or point mutations in RAI1. We present data on two cases of Smith-Magenis syndrome with mutation of RAI1. Both cases are phenotypically consistent with SMS and RAI1 mutation but also have other anomalies not previously reported in SMS, including spontaneous pneumothoraces. These cases also illustrate variability in the SMS phenotype not previously shown for RAI1 mutation cases, including hearing loss, absence of self-abusive behaviours, and mild global delays. Sequencing of RAI1 revealed mutation of the same heptameric C-tract (CCCCCCC) in exon 3 in both cases (c.3103delC one case and and c.3103insC in the other), resulting in frameshift mutations. Of the seven reported frameshift mutations occurring in poly C-tracts in RAI1, four cases (~57%) occur at this heptameric C-tract. Collectively, these results indicate that this heptameric C-tract is a preferential hotspot for single nucleotide insertion/deletions (SNindels) and therefore, should be considered a primary target for analysis in patients suspected for mutations in RAI1. We expect that as more patients are sequenced for mutations in RAI1, the incidence of frameshift mutations in this hotspot will become more evident.

| S-EPMC2964533 | biostudies-literature

RAI1 variations in Smith-Magenis syndrome patients without 17p11.2 deletions.

Project description:BackgroundSmith-Magenis syndrome (SMS) (OMIM No 182290) is a mental retardation syndrome characterised by behavioural abnormalities, including self injurious behaviours, sleep disturbance, and distinct craniofacial and skeletal anomalies. It is usually associated with deletion involving 17p11.2 and is estimated to occur in 1/25,000 births. Heterozygous frameshift mutations leading to protein truncation in retinoic acid induced 1 gene (RAI1) have been identified in individuals with phenotypic features consistent with SMS. RAI1 lies within the 17p11.2 locus, but these patients did not have 17p11.2 deletions.ObjectiveAnalysis of four individuals with features consistent with SMS for variations in RAI1, using a polymerase chain reaction and sequencing strategy. None of these patients carry 17p11.2 deletions.ResultsTwo patients had small deletions in RAI1 resulting in frameshift and premature truncation of the protein. Missense mutations were identified in the other two. Orthologs across other genomes showed that these missense mutations occurred in identically conserved regions of the gene. The mutations were de novo, as all parental samples were normal. Several polymorphisms were also observed, including new and reported SNPs. The patients' clinical features differed from those found in 17p11.2 deletion by general absence of short stature and lack of visceral anomalies. All four patients had developmental delay, reduced motor and cognitive skills, craniofacial and behavioural anomalies, and sleep disturbance. Seizures, not previously thought to be associated with RAI1 mutations, were observed in one patient of the cohort.ConclusionsHaploinsufficiency of the RAI1 gene is associated with most features of SMS, including craniofacial, behavioural, and neurological signs and symptoms.

| S-EPMC1735950 | biostudies-literature

Possible underreporting of pathogenic variants in RAI1 causing Smith-Magenis syndrome.

Project description: Not available

| S-EPMC8519085 | biostudies-literature

Neurodevelopmental Disorders Associated with Abnormal Gene Dosage: Smith-Magenis and Potocki-Lupski Syndromes.

Project description:Smith-Magenis syndrome (SMS) and Potocki-Lupski syndrome (PTLS) are reciprocal contiguous gene syndromes within the well-characterized 17p11.2 region. Approximately 3.6 Mb microduplication of 17p11.2, known as PTLS, represents the mechanistically predicted homologous recombination reciprocal of the SMS microdeletion, both resulting in multiple congenital anomalies. Mouse model studies have revealed that the retinoic acid-inducible 1 gene (RAI1) within the SMS and PTLS critical genomic interval is the dosage-sensitive gene responsible for the major phenotypic features in these disorders. Even though PTLS and SMS share the same genomic region, clinical manifestations and behavioral issues are distinct and in fact some mirror traits may be on opposite ends of a given phenotypic spectrum. We describe the neurobehavioral phenotypes of SMS and PTLS patients during different life phases as well as clinical guidelines for diagnosis and a multidisciplinary approach once diagnosis is confirmed by array comparative genomic hybridization or RAI1 gene sequencing. The main goal is to increase awareness of these rare disorders because an earlier diagnosis will lead to more timely developmental intervention and medical management which will improve clinical outcome.

| S-EPMC4918721 | biostudies-literature

Molecular and Neural Functions of Rai1, the Causal Gene for Smith-Magenis Syndrome.

Project description:Haploinsufficiency of Retinoic Acid Induced 1 (RAI1) causes Smith-Magenis syndrome (SMS), which is associated with diverse neurodevelopmental and behavioral symptoms as well as obesity. RAI1 encodes a nuclear protein but little is known about its molecular function or the cell types responsible for SMS symptoms. Using genetically engineered mice, we found that Rai1 preferentially occupies DNA regions near active promoters and promotes the expression of a group of genes involved in circuit assembly and neuronal communication. Behavioral analyses demonstrated that pan-neural loss of Rai1 causes deficits in motor function, learning, and food intake. These SMS-like phenotypes are produced by loss of Rai1 function in distinct neuronal types: Rai1 loss in inhibitory neurons or subcortical glutamatergic neurons causes learning deficits, while Rai1 loss in Sim1+ or SF1+ cells causes obesity. By integrating molecular and organismal analyses, our study suggests potential therapeutic avenues for a complex neurodevelopmental disorder.

| S-EPMC5098476 | biostudies-literature

RAI1 transcription factor activity is impaired in mutants associated with Smith-Magenis Syndrome.

Project description:Smith-Magenis Syndrome (SMS) is a complex genomic disorder mostly caused by the haploinsufficiency of the Retinoic Acid Induced 1 gene (RAI1), located in the chromosomal region 17p11.2. In a subset of SMS patients, heterozygous mutations in RAI1 are found. Here we investigate the molecular properties of these mutated forms and their relationship with the resulting phenotype. We compared the clinical phenotype of SMS patients carrying a mutation in RAI1 coding region either in the N-terminal or the C-terminal half of the protein and no significant differences were found. In order to study the molecular mechanism related to these two groups of RAI1 mutations first we analyzed those mutations that result in the truncated protein corresponding to the N-terminal half of RAI1 finding that they have cytoplasmic localization (in contrast to full length RAI1) and no ability to activate the transcription through an endogenous target: the BDNF enhancer. Similar results were found in lymphoblastoid cells derived from a SMS patient carrying RAI1 c.3103insC, where both mutant and wild type products of RAI1 were detected. The wild type form of RAI1 was found in the chromatin bound and nuclear matrix subcellular fractions while the mutant product was mainly cytoplasmic. In addition, missense mutations at the C-terminal half of RAI1 presented a correct nuclear localization but no activation of the endogenous target. Our results showed for the first time a correlation between RAI1 mutations and abnormal protein function plus they suggest that a reduction of total RAI1 transcription factor activity is at the heart of the SMS clinical presentation.

| S-EPMC3445574 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data