Related Experiment Video
Updated: May 24, 2026
Behavioral Characterization of an Angelman Syndrome Mouse Model
Published on: October 20, 2023
[Prader-Willi and Angelman syndromes: 21 years of experience]
D Royo Pérez1, L Monge Galindo, J López Pisón
1Sección Neuropediatría, Hospital Universitario Miguel Servet, Zaragoza, España.
Insights
Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are imprinting disorders. Our 21-year study found PWS patients more commonly had uniparental disomy, unlike typical literature findings, while AS patients frequently had maternal deletions.
Area of Science:
- Genetics
- Developmental Biology
- Pediatrics
Context:
- Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are the first identified human imprinting disorders.
- Genomic imprinting is crucial for normal development, and its disruption leads to PWS and AS.
- Understanding the genetic basis of PWS and AS is essential for diagnosis and management.
Purpose:
- To review a 21-year experience with genetically confirmed cases of PWS and AS.
- To analyze the genetic causes and clinical characteristics of PWS and AS patients.
- To compare findings with existing literature and discuss genotype-phenotype correlations.
Summary:
- This study analyzed 11 PWS patients (72.7% with uniparental disomy) and 6 AS patients (83.3% with maternal deletion).
- Contrary to literature, uniparental disomy was more prevalent in PWS cases in this cohort.
- Genotype-phenotype correlations suggest deletions worsen PWS, while uniparental disomy may be milder in AS.
Impact:
- Highlights the importance of genetic testing for accurate PWS and AS diagnosis, especially in cases of unexplained hypotonia or developmental delays.
- Provides valuable data on the prevalence of genetic causes in PWS and AS, challenging existing literature.
- Emphasizes the need for early genetic counseling based on clinical symptoms to prevent diagnostic delays and unnecessary investigations.
Introduction:
Prader-Willi syndrome (PWS) and Angelman syndrome (AS) were the first syndromes in humans that were known to originate from the phenomenon of the genomic imprinting. We review our experience of 21 years with PWS and AS that were confirmed with the genetically.
Results:
Of the 13,875 patients recorded during the study period, 11 were diagnosed with PWS (18%), 7 males (63.6%) and 4 females (36.4%), with a mean age of 9.06 years (+/- 6.92, range: 0.68-21.6). The time of the follow up of this group was 3.83 years (+/- 4.03, range: 0.49-15.3), and the age at diagnosis was 4.4 years (+/- 6.84, range: 0.03-19.38). Almost three quarters (72.7% of the PWS patients had a uniparental dysomy and 27.3% a paternal deletion. Six patients (8%) were diagnosed with AS, 4 females (66.6%) and 2 males (33.4%), with a mean age of 14.65 years (+/- 11.89, range: 1.3-30.7). The time of follow up was 6.76 years (+/- 5.89,range: 0.16-15), and the age at diagnosis was 8.84 years (+/- 9.11, range: 1.10-23). A maternal deletion was present in 83.3% of the AS patients and 16.7% had a maternal dysomy.
Discussion:
As genetic advances are made these pathologies are confirmed before. Unlike the data in the literature, in our series most patients diagnosed with PWS (72'3%) had uniparental disomy. Recent studies correlation genotype with phenotype, in PWS is more serious if it occurs a deletion and in SA is milder in the case of uniparental disomy.
Conclusions:
Genetic studies must be performed in view of the established clinical symptoms: neonatal hypotonia of unknown cause in PWS and psychomotor deficits with autism features, particularly associated with epilepsy, must be evaluated in AS to prevent diagnostic uncertainties, unnecessary complementary examinations and to provide early genetic counselling.
