12
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Unmet clinical needs and burden in Angelman syndrome: a review of the literature

      review-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background

          Angelman syndrome (AS) is a rare disorder with a relatively well-defined phenotype. Despite this, very little is known regarding the unmet clinical needs and burden of this condition, especially with regard to some of the most prevalent clinical features—movement disorders, communication impairments, behavior, and sleep.

          Main text

          A targeted literature review using electronic medical databases (e.g., PubMed) was conducted to identify recent studies focused on specific areas of the AS phenotype (motor, communication, behavior, sleep) as well as epidemiology, diagnostic processes, treatment, and burden. 142 articles were reviewed and summarized. Findings suggest significant impairment across the life span in all areas of function. While some issues may resolve as individuals get older (e.g., hyperactivity), others become worse (e.g., movement disorders, aggression, anxiety). There are no treatments focused on the underlying etiology, and the symptom-based therapies currently prescribed do not have much, if any, empirical support.

          Conclusions

          The lack of standardized treatment protocols or approved therapies, combined with the severity of the condition, results in high unmet clinical needs in the areas of motor functioning, communication, behavior, and sleep for individuals with AS and their families.

          Related collections

          Most cited references108

          • Record: found
          • Abstract: found
          • Article: not found

          De novo truncating mutations in E6-AP ubiquitin-protein ligase gene (UBE3A) in Angelman syndrome.

          Angelman syndrome (AS) is associated with maternal deletions of human chromosome 15q11-q13 and with paternal uniparental disomy for this region indicating that deficiency of an imprinted, maternally expressed gene within the critical interval is the likely cause of the syndrome. Although the gene for E6-AP ubiquitin-protein ligase (UBE3A) was mapped to the critical region for AS, evidence of expression from both parental alleles initially suggested that it was an unlikely candidate gene for this disorder. Because attempts to identify any novel maternally expressed transcripts were unsuccessful and because the UBE3A gene remained within a narrowed AS critical region, we searched for mutations in UBE3A in 11 AS patients without known molecular defects (large deletion, uniparental disomy, or imprinting mutation). This analysis tested the possibility that deficiency of an undefined, maternally expressed transcript or isoform of the UBE3A gene could cause AS. Four mutations were identified including a de novo frameshift mutation and a de novo nonsense mutation in exon 3 and two missense mutations of less certain significance. The de novo truncating mutations indicate that UBE3A is the AS gene and suggest the possibility of a maternally expressed gene product in addition to the biallelically expressed transcript. Intragenic mutation of UBE3A in AS is the first example of a genetic disorder of the ubiquitin-dependent proteolytic pathway in mammals. It may represent an example of a human genetic disorder associated with a locus producing functionally distinct imprinted and biallelically expressed gene products.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Angelman syndrome 2005: updated consensus for diagnostic criteria.

            In 1995, a consensus statement was published for the purpose of summarizing the salient clinical features of Angelman syndrome (AS) to assist the clinician in making a timely and accurate diagnosis. Considering the scientific advances made in the last 10 years, it is necessary now to review the validity of the original consensus criteria. As in the original consensus project, the methodology used for this review was to convene a group of scientists and clinicians, with experience in AS, to develop a concise consensus statement, supported by scientific publications where appropriate. It is hoped that this revised consensus document will facilitate further clinical study of individuals with proven AS, and assist in the evaluation of those who appear to have clinical features of AS but have normal laboratory diagnostic testing.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Angelman syndrome - insights into a rare neurogenetic disorder.

              Angelman syndrome is a rare neurogenetic disorder that is characterized by microcephaly, severe intellectual deficit, speech impairment, epilepsy, EEG abnormalities, ataxic movements, tongue protrusion, paroxysms of laughter, abnormal sleep patterns, and hyperactivity. Angelman syndrome results from loss of function of the imprinted UBE3A (ubiquitin-protein ligase E3A) gene on chromosome 15q11.2-q13. This loss of function can be caused by a mutation on the maternal allele, a 5-7 Mb deletion of the maternally inherited chromosomal region, paternal uniparental disomy of chromosome 15, or an imprinting defect. The chromosomal deletion tends to cause the most severe symptoms, possibly owing to co-deletion of GABA receptor genes. UBE3A mutations and imprinting defects can be associated with a high risk of recurrence within families. Disruption of UBE3A function in neurons seems to inhibit synapse formation and experience-dependent synapse remodelling. Clinical diagnosis of Angelman syndrome in infants and young children is sometimes difficult, but can be verified by genetic tests. At present, treatment of symptoms such as seizures is the only medical strategy, but genetic therapies aimed at activating the silent copy of UBE3A on the paternal allele are conceivable.
                Bookmark

                Author and article information

                Contributors
                +1.919.541.7127 , acwheeler@rti.org
                psacco@rti.org
                rcabo@ovidrx.com
                Journal
                Orphanet J Rare Dis
                Orphanet J Rare Dis
                Orphanet Journal of Rare Diseases
                BioMed Central (London )
                1750-1172
                16 October 2017
                16 October 2017
                2017
                : 12
                : 164
                Affiliations
                [1 ]ISNI 0000000100301493, GRID grid.62562.35, RTI International, ; 3040 Cornwallis Road, PO Box 12194, Research Triangle Park, NC 27709-2194 USA
                [2 ]ISNI 0000000100301493, GRID grid.62562.35, RTI Health Solutions, ; 200 Park Offices Drive, Research Triangle Park, NC 27709 USA
                [3 ]Ovid Therapeutics Inc., 1460 Broadway, New York, NY 10036 USA
                Article
                716
                10.1186/s13023-017-0716-z
                5644259
                29037196
                dc25342b-9388-403d-8edd-12c7bf9f0706
                © The Author(s). 2017

                Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License ( http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

                History
                : 12 May 2017
                : 5 October 2017
                Funding
                Funded by: Ovid Therapuetics
                Award ID: NA
                Categories
                Review
                Custom metadata
                © The Author(s) 2017

                Infectious disease & Microbiology
                angleman syndrome,burden,unmet clinical needs,clinical features,treatments

                Comments

                Comment on this article