Caregivers Report on the Pathway to a Formal Diagnosis of Angelman Syndrome: A Comparison Across Genetic Etiologies within the Global Angelman Syndrome Registry

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Angelman syndrome (AS) and is typically diagnosed in children under the age of three based upon early behavioural concerns identified by parents, or genetic links with other family members. For some families however, the pathway to diagnosis is not so clear, particularly when children demonstrate differential characteristics, commonly seen for those with UBE3A pathogenic variants (ubiquitin protein ligase EA3), imprinting defects or uniparental disomy (patUPD) etiology. The aim of this paper is to explore parent’s experiences of the pathway to diagnosis involving 394 children with formal diagnoses of AS.

Data from the Global Angelman Syndrome Registry on the age of formal diagnosis, the process involved in formal diagnosis, professionals involved in the diagnosis, the number of tests taken and the prevalence of misdiagnoses were compared across deletion and non-deletion (UBE3A pathogenic variant, imprinting and patUPD) etiologies.

Compared to those with deletion etiology, individuals with non-deletions are more likely to (a) receive a diagnosis later in childhood (i.e., past the age of 3 years old), (b) have a greater number of professionals and tests involved and (c) to be misdiagnosed with global developmental delay.

The methods identified for formal diagnoses mirrored the current advances in technology and accessibility. The benefit of using parental report from registries to understand the diagnostic process and promote early and accurate diagnosis of AS is discussed.

Data Availability

This data is available on request to the data management committee. Please email for requests.


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We would like to thank the parents and children for the time they took to complete the registry.

Author information

Centre for Children’s Health Research, The University of Queensland, Brisbane, Australia
Laura Roche, Megan Tones & Helen Heussler

School of Education, University of Newcastle, University Drive, Callaghan, NSW, 2308, Australia
Laura Roche

Queensland University of Technology, Brisbane, Australia
Megan Tones

Developmental Disorders Group, Mater Research Institute, The University of Queensland, Brisbane, Australia
Mark G. Williams

Foundation for Angelman Syndrome Therapeutics (FAST), Salisbury, Australia
Meagan Cross & Chloe Simons

Children’s Health Queensland, Brisbane, Australia
Helen Heussler

LR: developed the concept and design for the study, assisted with the analysis of results, and wrote the manuscript. MT: assisted in the concept and design of the study, analysed the data, collaborated in writing the manuscript, and is the curator of the Global Angelman Syndrome Registry. MGW: provided expert sections on the genetic mechanisms of diagnosing Angelman syndrome and collaborated in the editing of the manuscript. MC and CS: assisted in the design of the original cohort, collaborated in the writing and editing of the manuscript. HS: assisted in the design of the original cohort, collaborated in the concept and design of the study and collaborated in the data analysis and editing of the manuscript.

Corresponding author
Correspondence to Laura Roche.

Ethics declarations

Ethical Approval
Ethics was approved by Mater Misericordiae Ltd Human Research Ethics Committee (approval number EC00332).

Consent statement
All participants provided informed consent via an electronic consent process. Participants were unable to view or complete registry modules without completion of the consent process.

Conflict of interest
The authors declare that they have no conflict of interest.

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