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Human cell line models, including the neuronal precursor line LUHMES, are important for investigating developmental transcriptional dynamics within imprinted regions, particularly the 15q11-q13 Angelman (AS) and Prader-Willi (PWS) syndrome locus. AS results from loss of maternal UBE3A in neurons, where the paternal allele is silenced by a convergent antisense transcript UBE3A-ATS, a lncRNA that terminates at PWAR1 in non-neurons. qRT-PCR analysis confirmed the exclusive and progressive increase in UBE3A-ATS in differentiating LUHMES neurons, validating their use for studying UBE3A silencing. Genome-wide transcriptome analyses revealed changes to 11 834 genes during neuronal differentiation, including the upregulation of most genes within the 15q11-q13 locus. To identify dynamic changes in chromatin loops linked to transcriptional activity, we performed a HiChIP validated by 4C, which identified two neuron-specific CTCF loops between MAGEL2-SNRPN and PWAR1-UBE3A. To determine if allele-specific differentially methylated regions (DMR) may be associated with CTCF loop anchors, whole genome long-read nanopore sequencing was performed. We identified a paternally hypomethylated DMR near the SNRPN upstream loop anchor exclusive to neurons and a paternally hypermethylated DMR near the PWAR1 CTCF anchor exclusive to undifferentiated cells, consistent with increases in neuronal transcription. Additionally, DMRs near CTCF loop anchors were observed in both cell types, indicative of allele-specific differences in chromatin loops regulating imprinted transcription. These results provide an integrated view of the 15q11-q13 epigenetic landscape during LUHMES neuronal differentiation, underscoring the complex interplay of transcription, chromatin looping, and DNA methylation. They also provide insights for future therapeutic approaches for AS and PWS.

Dopamine (DA) plays important roles in various behaviors, including learning and motivation. Recently, THOC5 was identified as an important regulator in the development of dopaminergic neurons. However, how THOC5 is regulated has not been explored. In this study, we found an interaction between THOC5 and necdin, which is encoded by a gene located in the chromosome deletion region of Prader-Willi syndrome (PWS), by using a yeast two-hybrid assay. Necdin affects the mRNA export function of THOC5 by regulating its nucleocytoplasmic localization. As a result, the expression of a few DA neuronal development-related genes, such as Mef2c, Lef1 and Prkcg, is altered in necdin-deficient mice. We also found neurodegeneration of dopaminergic neurons and an increase of glial cells in necdin-deficient mice, which may underlie the dyspraxia behaviors in these mice. Our results thus identified necdin as a novel regulator for THOC5, which may underlie, at least partly, the abnormal DA neuron development in necdin-deficient mice. [ABSTRACT FROM AUTHOR]

Patients with genetic syndromes require special dental attention because they have symptoms that promote plaque accumulation, dental erosion, dental caries and gingival diseases. The aim of the study was to assess hygienic behaviors, use of dental care and frequency of professional preventive procedures among Polish children and adolescents with Prader-Willi, Down, Angelman, Silver-Russell and Smith-Lemli-Opitz syndromes. Parents/legal guardians of children and adolescents with genetic syndromes were included. A questionnaire survey was conducted regarding socioeconomic factors, hygienic procedures performed at home and use of dental care as well as use of preventive treatments. The percentage of patients with genetic syndromes who received dental care was statistically significantly lower compared to the control group. Oral hygiene measures were most frequently used by participants with Silver-Russel syndrome, and less commonly by patients with Prader-Willi and Down syndrome. Dental treatment under general anesthesia was provided in 26 (38.2%) of the 68 children with genetic syndromes receiving dental care. Hygienic neglect and inadequate use of dental care due to limited access to certain preventive and therapeutic procedures among patients with genetic syndromes are worrying. It is necessary to educate and intensify caries prevention in this group of patients. [ABSTRACT FROM AUTHOR]

Background: To evaluate the impact of coronavirus disease 2019 (COVID-19) on polysomnographic evaluation in patients with Prader-Willi syndrome (PWS). Patients and methods: A retrospective cohort study of two consecutive overnight polysomnograms (PSG) in 92 PWS patients (mean age 9.1, range 3.1–22 years). 57/92 participants (35 female) had a COVID-19 infection between the two consecutive examinations. 35 patients (21 female) had no infection (control group). Distribution of genetics was as follows: 13/57 (22.8%) deletion, 19/57 (33.3%) uniparental disomy, 2/57 (3,5%) imprinting defect, 3/57 (5.3%) non-deletion, 20/57 (35.1%) diagnosed by analyses of the methylation pattern of chromosome 15q11-13. Mean time interval between COVID-19 infection and post-COVID-19 evaluation was 96.2 days. Results: Course of COVID-19 infection was asymptomatic 8/82 (9.8%), mild 63/82 (76.8%), medium 11/84 (13.4%). The five most frequently experienced symptoms in PWS patients were fever (56.1%); headache (45.1%); cold (42.7%); cough (31.7%) and body aches (21.95%). PWS patients who had COVID-19 infection had significantly lower mean oxygen saturation (SpO2) measured by pulse oximetry (post 94.8% vs. pre 95.7%, p = 0.001), lower detected lowermost SpO2 (post 86.2 vs. pre 87.3%, p = 0.003), and higher occurrence of hypopnoea (post 13.9 vs. pre 10.7, p = 0.001). Time in optimal SpO2 (95–100%) decreased significantly (post 54.3% vs. pre 73.8%, p = 0.001), whereas an increase was observed in time in suboptimal SpO2 (90–95%) (post 45.5% vs. 25.8%, p = 0.001) and in time in poor SpO2 (< 90%) (post 0.7% vs. pre 0.2%, p = 0.030). Body-Mass-Index (BMI)-SDS for PWS showed no differences between the groups at any time. BMI-SDS-differences showed no influence on differences in SpO2 evaluations. In the genetic subgroup with deletion there was a statistically significant effect on an increased number of OSA (p = 0.027). The genetic subgroup with uniparental disomy (UPD) was associated with a reduced risk of higher HF (p = 0.035) and less hypopnea (p = 0.011). Conclusion: PWS patients predominantly experienced only mild to medium symptoms during COVID-19 infection without necessity of hospitalisation. However, on average three months after infection, differences in PSG evaluations were still apparent, manifesting in lower SpO2 and more frequent hypopnea. A long-lasting impairment of the pulmonary system due to the COVID-19 infection might be responsible. [ABSTRACT FROM AUTHOR]

Temple syndrome is a rare imprinting disorder, caused by alterations in the critical imprinted region 14q32 of chromosome 14. It is characterized by pre- and postnatal growth retardation, truncal hypotonia and facial dysmorphism in the neonatal period. We report an 18-year-old girl with a late diagnosis of Temple syndrome presenting with all typical signs and symptoms including small for gestational age at birth, feeding difficulties, muscle hypotonia and delayed developmental milestones, central precocious puberty, truncal obesity and reduced growth. The patient is the second reported in the literature with signs of clinical and biochemical hyperandrogenism and the first treated with Dehydrocortisone®, with a good response. The clinical diagnosis of this patient was made after long-term follow up at a single center for rare endocrine diseases, and a molecular genetics diagnosis of complete hypomethylation of 14q32 chromosome imprinting center (DLK/GTL2) was recently established. Growth hormone treatment was not given and although precocious puberty was treated in line with standard protocols, her final height remained below the target range. Increased awareness of Temple syndrome and timely molecular diagnosis enables improvement of clinical care of these patients as well as prevention of inherent metabolic consequences. [ABSTRACT FROM AUTHOR]

In the snoRNA host gene SNHG14, 29 consecutive introns each generate SNORD116, and 48 tandem introns encode SNORD115. Loss of SNORD116 expression, but not of SNORD115, is linked to the neurodevelopmental disease Prader-Willi syndrome. SNORD116 and SNORD115 resemble box C/D small nucleolar RNAs (snoRNAs) but lack known targets. Both were strongly accumulated during neuronal differentiation, but with distinct mechanisms: Increased host-gene expression for SNORD115 and apparent stabilization for SNORD116. For functional characterization we created cell lines specifically lacking the expressed, paternally inherited, SNORD115 or SNORD116 cluster. Analyses during neuronal development indicates changes in RNA stability and protein synthesis. These data suggest that the loss of SNORD116 enhances some aspects of developmental timing of neuronal cells. Altered mRNAs include MAGEL2, causal in the PWS-like disorder Schaaf-Yang syndrome. Comparison of SNORD115 and SNORD116 mutants identifies small numbers of altered mRNAs and ncRNAs. These are enriched for functions potentially linked to PWS phenotypes and include protocadherins, which are key cell signalling factors during neurodevelopment. Loss of an snoRNA causes the neurodevelopmental disease Prader-Willi Syndrome (PWS). Here the authors generate snoRNA-deleted pre-neuronal cell lines. Small numbers of RNAs and proteins were altered, with functions potentially linked to PWS symptoms. [ABSTRACT FROM AUTHOR]

Background/objectives: Euchromatic histone lysine methyltransferase 2 (EHMT2, also known as G9a) is a mammalian histone methyltransferase that catalyzes the dimethylation of histone 3 lysine 9 (H3K9). On human chromosome 15, the parental-specific expression of Prader–Willi Syndrome (PWS)-related genes, such as SNRPN and SNORD116, are regulated through the genetic imprinting of the PWS imprinting center (PWS-IC). On the paternal allele, PWS genes are expressed whereas the epigenetic maternal silencing of PWS genes is controlled by the EHMT2-mediated methylation of H3K9 in PWS-IC. Here, we measured the effects of RNA interference of EHMT2 on the maternal expression of genes deficient in PWS in mouse model and patient iPSC-derived cells. Methods: We used small interfering RNA (siRNA) oligonucleotides and lentiviral short harpin RNA (shRNA) to reduce Ehtm2/EHMT2 expression in mouse Snord116 deletion primary neurons, PWS patient-derived induced pluripotent stem cell (iPSC) line and PWS iPSC-derived neurons. We then measured the expression of transcript or protein (if relevant) of PWS genes normally silenced on the maternal allele. Results: With an approximate reduction of 90% in EHMT2 mRNA and more than 80% of the EHMT2 protein, we demonstrated close to a 2-fold increase in the expression of maternal transcripts for SNRPN and SNORD116 in PWS iPSCs treated with siEHMT2 compared to PWS iPSC siControl. A similar increase in SNORD116 and SNRPN RNA expression was observed in PWS iPSC-derived neurons treated with shEHMT2. Conclusions: RNAi reduction in EHMT2 activates maternally silenced PWS genes. Further studies are needed to determine whether the increase is therapeutically relevant. This study confirms the role of EHMT2 in the epigenetic regulation of PWS genes. [ABSTRACT FROM AUTHOR]

Angelman syndrome (AS) and Prader-Willi syndrome (PWS), two distinct neurodevelopmental disorders, result from loss of expression from imprinted genes in the chromosome 15q11-13 locus most commonly caused by a megabase-scale deletion on either the maternal or paternal allele, respectively. Each occurs at an approximate incidence of 1/15,000 to 1/30,000 live births and has a range of debilitating phenotypes. Patient-derived induced pluripotent stem cells (iPSCs) have been valuable tools to understand human-relevant gene regulation at this locus and have contributed to the development of therapeutic approaches for AS. Nonetheless, gaps remain in our understanding of how these deletions contribute to dysregulation and phenotypes of AS and PWS. Variability across cell lines due to donor differences, reprogramming methods, and genetic background make it challenging to fill these gaps in knowledge without substantially increasing the number of cell lines used in the analyses. Isogenic cell lines that differ only by the genetic mutation causing the disease can ease this burden without requiring such a large number of cell lines. Here, we describe the development of isogenic human embryonic stem cell (hESC) lines modeling the most common genetic subtypes of AS and PWS. These lines allow for a facile interrogation of allele-specific gene regulation at the chromosome 15q11-q13 locus. Additionally, these lines are an important resource to identify and test targeted therapeutic approaches for patients with AS and PWS. [ABSTRACT FROM AUTHOR]

Abstract Background To evaluate the impact of coronavirus disease 2019 (COVID-19) on polysomnographic evaluation in patients with Prader-Willi syndrome (PWS). Patients and methods A retrospective cohort study of two consecutive overnight polysomnograms (PSG) in 92 PWS patients (mean age 9.1, range 3.1–22 years). 57/92 participants (35 female) had a COVID-19 infection between the two consecutive examinations. 35 patients (21 female) had no infection (control group). Distribution of genetics was as follows: 13/57 (22.8%) deletion, 19/57 (33.3%) uniparental disomy, 2/57 (3,5%) imprinting defect, 3/57 (5.3%) non-deletion, 20/57 (35.1%) diagnosed by analyses of the methylation pattern of chromosome 15q11-13. Mean time interval between COVID-19 infection and post-COVID-19 evaluation was 96.2 days. Results Course of COVID-19 infection was asymptomatic 8/82 (9.8%), mild 63/82 (76.8%), medium 11/84 (13.4%). The five most frequently experienced symptoms in PWS patients were fever (56.1%); headache (45.1%); cold (42.7%); cough (31.7%) and body aches (21.95%). PWS patients who had COVID-19 infection had significantly lower mean oxygen saturation (SpO2) measured by pulse oximetry (post 94.8% vs. pre 95.7%, p = 0.001), lower detected lowermost SpO2 (post 86.2 vs. pre 87.3%, p = 0.003), and higher occurrence of hypopnoea (post 13.9 vs. pre 10.7, p = 0.001). Time in optimal SpO2 (95–100%) decreased significantly (post 54.3% vs. pre 73.8%, p = 0.001), whereas an increase was observed in time in suboptimal SpO2 (90–95%) (post 45.5% vs. 25.8%, p = 0.001) and in time in poor SpO2 (

Prader-Willi Syndrome (PWS) is a rare disorder that was initially documented by Prader and Willi in 1956. Despite significant advancements in the understanding of PWS over recent decades, no bibliometric studies have been reported on this field. We aimed to analyze and explore the research trends and hotspots of PWS using a bibliometric analysis to understand the future development of basic and clinical research.

Abstract Background Prader-Willi syndrome (PWS) is a rare multisystemic hereditary illness. Recombinant human growth hormone (rhGH) therapy is widely recognized as the primary treatment for PWS. This study aimed to examine how different PWS genotypes influence the outcome of rhGH treatment in children with PWS. Methods A review was conducted on 146 Chinese children with PWS, genetically classified and monitored from 2017 to 2022. Unaltered and modified generalized estimating equations (GEE) were employed to examine the long-term patterns in primary outcomes (growth metrics) and secondary outcomes (glucose metabolism metrics and insulin-like growth factor-1 (IGF-1)) during rhGH therapy. The study also evaluated the prevalence of hypothyroidism, hip dysplasia, and scoliosis before and after rhGH treatment. Results Children with PWS experienced an increase in height/length standard deviation scores (SDS) following rhGH administration. The impact of rhGH therapy on growth measurements was similar in both the deletion and maternal uniparental diploidy (mUPD) cohorts. Nevertheless, the deletion group was more prone to insulin resistance (IR) compared to the mUPD group. No significant variations in growth metrics were noted between the two groups (P > 0.05). At year 2.25, the mUPD group showed a reduction in fasting insulin (FINS) levels of 2.14 uIU/ml (95% CI, -4.26, -0.02; P = 0.048) and a decrease in homeostasis model assessment of insulin resistance (HOMA-IR) of 0.85 (95% CI, -1.52, -0.17; P = 0.014) compared to the deletion group. Furthermore, there was a decrease in the IGF standard deviation scores (SDS) by 2.84 (95% CI, -4.84, -0.84; P = 0.005) in the mUPD group during the second year. The frequency of hip dysplasia was higher in the mUPD group compared to the deletion group (P

Abstract Background Prader-Willi syndrome (PWS) is a rare genetic neurodevelopmental disorder. Individuals with PWS face a range of cognitive, behavioral, and emotional challenges that require comprehensive and lifelong care, posing significant demands on their caregivers. The study is not only aimed to assess the psychological conditions of caregivers of adult subjects with PWS focusing on psychological distress and coping, but also to shed light on a crucial yet often overlooked aspect of healthcare. This study aims to compare the psychological well-being of individuals with PWS and their caregivers, providing valuable insights that can potentially improve the quality of care for these individuals. The sample recruited at the Division of Auxology, IRCCS Istituto Auxologico Italiano, was composed of 30 adult subjects with PWS (11 men and 19 women; mean age ± SD: 36.4 ± 10.31 years; mean Body Mass Index (BMI): 35.7 ± 8.92: kg/m2) and their caregivers (10 men and 20 women). To assess the psychological condition of caregivers, the Italian-validated versions of the Depression Anxiety and Stress Scale (DASS-21) and the Coping Orientation to the Problems Experiences (COPE) were used, while to assess the psychological well-being of individuals with PWS and their caregivers, the Italian validated version of the Psychological General Well-Being Index (PGWBI) was used. Results Depression (p

Background: Prader-Willi syndrome (PWS) is a rare genetic neurodevelopmental disorder. Individuals with PWS face a range of cognitive, behavioral, and emotional challenges that require comprehensive and lifelong care, posing significant demands on their caregivers. The study is not only aimed to assess the psychological conditions of caregivers of adult subjects with PWS focusing on psychological distress and coping, but also to shed light on a crucial yet often overlooked aspect of healthcare. This study aims to compare the psychological well-being of individuals with PWS and their caregivers, providing valuable insights that can potentially improve the quality of care for these individuals. The sample recruited at the Division of Auxology, IRCCS Istituto Auxologico Italiano, was composed of 30 adult subjects with PWS (11 men and 19 women; mean age ± SD: 36.4 ± 10.31 years; mean Body Mass Index (BMI): 35.7 ± 8.92: kg/m2) and their caregivers (10 men and 20 women). To assess the psychological condition of caregivers, the Italian-validated versions of the Depression Anxiety and Stress Scale (DASS-21) and the Coping Orientation to the Problems Experiences (COPE) were used, while to assess the psychological well-being of individuals with PWS and their caregivers, the Italian validated version of the Psychological General Well-Being Index (PGWBI) was used. Results: Depression (p < 0.001), Stress (p = 0.050), and Total score (p = 0.009) of DASS 21 were higher in the caregivers of subjects with PWS than in the general population. PGWBI scores of caregivers were significantly lower than in individuals with PWS in Positive Well-being (p < 0.001), General Health (p = 0.006), Vitality (p = 0.004), and the total score (p = 0.006). The depression subscale of PGWBI was higher in caregivers than in subjects with PWS. Correlations between the subscales of COPE and the total score of PGWBI in caregivers revealed that the Avoidance subscale of COPE had a negative significant correlation with the total score of PGWBI (p = 0.003). Conclusions: Our results highlighted several critical insights into the profound emotional and psychological challenges faced by the caregivers of individuals with PWS. [ABSTRACT FROM AUTHOR]

Exercise for people with Prader-Willi syndrome (PWS) is important for their health and wellbeing and can provide opportunities for community participation. However, they may find it difficult to participate in some contexts, such as community gyms because social and environmental barriers in these settings may compound difficulties caused by physical impairments or intellectual disability. This study aims to observe and understand the actions and interactions of people with PWS when they exercise in community gyms. A focussed ethnographic study will be conducted. Field notes will be taken in community gyms where people with PWS are participating in a structured exercise program for six months as part of a randomised control trial called PRESTO. Up to ten participants will be observed, with at least three observations planned per participation during the program. Gym sessions observed will be approximately 1 hour long. Within the framework of interpretive description, reflective thematic analysis will be used to interpret observational data. Our findings will inform how best to support people with PWS to exercise at a community gym. Trial Registration Number: ACTRN12620000416998; Australian and New Zealand Clinical Trial Registry. [ABSTRACT FROM AUTHOR]

Background: Multi-locus imprinting disturbance (MLID) with methylation defects in various differentially methylated regions (DMRs) has recently been identified in approximately 150 cases with imprinting disorders (IDs), and deleterious variants have been found in genes related to methylation maintenance of DMRs, such as those encoding proteins constructing the subcortical maternal complex (SCMC), in a small fraction of patients and/or their mothers. However, integrated methylation analysis for DMRs and sequence analysis for MLID-causative genes in MLID cases and their mothers have been performed only in a single study focusing on Beckwith-Wiedemann syndrome (BWS) and Silver-Russell syndrome (SRS) phenotypes. Results: Of 783 patients with various IDs we have identified to date, we examined a total of 386 patients with confirmed epimutation and 71 patients with epimutation or uniparental disomy. Consequently, we identified MLID in 29 patients with epimutation confirmed by methylation analysis for multiple ID-associated DMRs using pyrosequencing and/or methylation-specific multiple ligation-dependent probe amplification. MLID was detected in approximately 12% of patients with BWS phenotype and approximately 5% of patients with SRS phenotype, but not in patients with Kagami-Ogata syndrome, Prader-Willi syndrome, or Angelman syndrome phenotypes. We next conducted array-based methylation analysis for 78 DMRs and whole-exome sequencing in the 29 patients, revealing hypomethylation-dominant aberrant methylation patterns in various DMRs of all the patients, eight probably deleterious variants in genes for SCMC in the mothers of patients, and one homozygous deleterious variant in ZNF445 in one patient. These variants did not show gene-specific methylation disturbance patterns. Clinically, neurodevelopmental delay and/or intellectual developmental disorder (ND/IDD) was observed in about half of the MLID patients, with no association with the identified methylation disturbance patterns and genetic variants. Notably, seven patients with BWS phenotype were conceived by assisted reproductive technology (ART). Conclusions: The frequency of MLID was 7.5% (29/386) in IDs caused by confirmed epimutation. Furthermore, we revealed diverse patterns of hypomethylation-dominant methylation defects, nine deleterious variants, ND/IDD complications in about half of the MLID patients, and a high frequency of MLID in ART-conceived patients. [ABSTRACT FROM AUTHOR]

Background: Prader–Willi syndrome (PWS) is a rare genetic disorder characterized by distinctive physical, cognitive, and behavioral manifestations, coupled with profound alterations in appetite regulation, leading to severe obesity and metabolic dysregulation. These clinical features arise from disruptions in neurodevelopment and neuroendocrine regulation, yet the molecular intricacies of PWS remain incompletely understood. Methods: This study aimed to comprehensively profile circulating neuromodulatory factors in the serum of 53 subjects with PWS and 34 patients with non-syndromic obesity, utilizing a proximity extension assay with the Olink Target 96 neuro-exploratory and neurology panels. The ANOVA p-values were adjusted for multiple testing using the Benjamani–Hochberg method. Protein–protein interaction networks were generated in STRING V.12. Corrplots were calculated with R4.2.2 by using the Hmisc, Performance Analytics, and Corrplot packages Results: Our investigation explored the potential genetic underpinnings of the circulating protein signature observed in PWS, revealing intricate connections between genes in the PWS critical region and the identified circulating proteins associated with impaired oxytocin, NAD metabolism, and sex-related neuromuscular impairment involving, CD38, KYNU, NPM1, NMNAT1, WFIKKN1, and GDF-8/MSTN. The downregulation of CD38 in individuals with PWS (p < 0.01) indicates dysregulation of oxytocin release, implicating pathways associated with NAD metabolism in which KYNU and NMNAT1 are involved and significantly downregulated in PWS (p < 0.01 and p < 0.05, respectively). Sex-related differences in the circulatory levels of WFIKKN1 and GDF-8/MSTN (p < 0.05) were also observed. Conclusions: This study highlights potential circulating protein biomarkers associated with impaired oxytocin, NAD metabolism, and sex-related neuromuscular impairment in PWS individuals with potential clinical implications. [ABSTRACT FROM AUTHOR]