American Journal of Medical Genetics Part A
○ Wiley
Preprints posted in the last 30 days, ranked by how well they match American Journal of Medical Genetics Part A's content profile, based on 17 papers previously published here. The average preprint has a 0.01% match score for this journal, so anything above that is already an above-average fit.
Petrin, A. L.; Keen, H. L.; Dunlay, L.; Xie, X. J.; Zeng, E.; Butali, A.; Wilcox, A.; Marazita, M. L.; Murray, J. C.; Moreno-Uribe, L.
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Introduction: Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is a common congenital malformation with complex etiology involving both genetic and environmental factors. Epigenetic mechanisms may mediate environmental contributions, but separating genetic from environmental effects remains challenging. Methods: We present an epigenome-wide association study with 32 monozygotic and 22 dizygotic twin pairs discordant for NSCL/P on blood and saliva samples. Differential methylation analysis was conducted using linear models to identify CpG sites showing significant methylation differences between affected and unaffected twins followed by functional annotation and pathway enrichment analysis. Results: The top-ranked finding is a differentially methylated region comprising two CpG sites at the CYP26A1 locus, cg12110262 (P = 3.21x10-7) and cg15055355 (P = 1.39x10-3). CYP26A1 is essential for retinoic acid catabolism and craniofacial patterning. The chromatin regulator ANKRD11, which causes KBG syndrome featuring cleft palate was the second best hit. Differentially methylated CpG sites showed significant enrichment in craniofacial enhancers and overlap with multiple GWAS-validated cleft genes including VAX1, PVRL1, SMAD3, and PRDM16. Conclusions: Our findings implicate retinoic acid signaling and chromatin regulation in NSCL/P etiology and demonstrate the value of discordant twin designs for distinguishing environmental from genetic epigenetic contributions to complex malformations.
Nordstrand, M.; Fajutrao Falk, S.; Johansson, M.; Pestoff, R.; Tammimies, K.
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Genetic counselling outcome measures are increasingly adapted for diverse clinical contexts. While the Genetic Counselling Outcome Scale (GCOS-24) is available in Swedish, no autism-specific version has been developed. Therefore, we adapted the Swedish GCOS-24 using the English version of the modified GCOS-24 (mGCSOS-24) to create a Swedish autism-specific mGCOS-24. Thereafter, we evaluated both the Swedish autism mGCOS-24 and the Swedish general GCOS-24 using Rasch analysis to assess their psychometric properties. Both instruments exhibited structural challenges, including multidimensionality, disordered thresholds, local item dependence, and invariance issues. For the Swedish autism mGCOS-24, we were able to identify subscales with acceptable measurement properties. However, applying the same structure to the Swedish general GCOS-24 did not resolve its broader limitations. This study introduces the first Swedish autism-specific mGCOS-24 and represents the first Rasch-based evaluation of any GCOS-24 or mGCOS-24 in Swedish. Our findings highlight important opportunities for measure refinement but also indicate that new or more substantially adapted tools may be needed to capture outcomes of genetic counselling in autistic populations.
Mossler, K.; D'Orazio, E.; Hall, K.; Osann, K.; Kimonis, V.; Quintero-Rivera, F.
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Objective The decline of the perinatal demise rate is slowing and demises are often unexplained. Significant research has been done regarding diagnostic yield and genetic causes of demise, but little is known about how Geneticist involvement impacts outcomes. The goal of the study was to evaluate post-mortem genetic testing practices and effects of the geneticists involvement. Methods Retrospective data from 111 perinatal demise cases was examined, including rates of prenatal genetic counseling, post-delivery genetics consult, genetic testing, and autopsy investigation. Results In this cohort 54% received genetic testing and 25% received a genetics consult. When compared to those without, cases with genetic specialist involvement were associated with significant increases in testing uptake (p=0.007), diagnostic yield (p<0.001), and patient education (p<0.001). Second trimester stillbirths and those with fewer ultrasound (US) abnormalities were less likely to receive genetic testing (both p values <0.001) and consults (p<0.001, p=0.020). Conclusion Though it was not possible to avoid ascertainment bias, this data demonstrates that geneticist involvement correlates with a higher rate of testing, greater diagnostic yield, and more thorough counseling. These findings underscore the importance of integrating genetics providers into perinatal postmortem healthcare teams.
Linntam, D.; Palumaa, K.; Palumaa, T.
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Background: Despite strong evidence from controlled trials, uncertainty remains about the real-world use of 0.05% atropine in patients with lighter irises due to tolerability concerns, and predictors of treatment response are poorly understood. Here, we evaluated the effectiveness, tolerability, and early biometric response to 0.05% atropine in clinical practice among patients with predominantly light irises. Methods: This prospective cohort study included 33 patients treated with 0.05% atropine (82% with light irises). Cycloplegic spherical equivalent refraction (SER) was measured at baseline and 3-month intervals. Axial length (AL), photopic pupil diameter, accommodation amplitude, and subjective side effects were monitored more frequently initially. Results: Median age at treatment initiation was 11.97 years, SER -5.38 D, and AL 25.42 mm. Over 12 months, SER changed by -0.078 {+/-} 0.349 D (mean {+/-} SD), and AL increased by 0.052 {+/-} 0.115 mm. Eighty-eight percent of participants had a SER change of <0.5 D, and 91% had axial elongation of <0.2 mm, indicating clinically limited myopia progression. Photopic pupil diameter was larger, and accommodation amplitude was reduced throughout follow-up. Early in treatment, side effects, including photophobia and near-work difficulties, were common but minimally disruptive. Their incidence decreased rapidly and rarely required treatment modification. In exploratory analyses, early AL changes predicted 12-month AL outcomes, with associations detectable as early as 1 week and strengthening over time. Conclusions: 0.05% atropine was well tolerated and effective in this population with light irises. Early AL changes may predict 12-month treatment response. These findings support the implementation of 0.05% atropine in routine clinical practice in populations with light irises and highlight the potential for early AL monitoring to guide timely treatment adjustments.
Liedtke, D.; Rak, K.; Schrode, K. M.; Hehlert, P.; Chamanrou, N.; Bengl, D.; Katana, R.; Heydaran, S.; Doll, J.; Han, M.; Nanda, I.; Senthilan, P. R.; Juergens, L.; Bieniussa, L.; Voelker, J.; Neuner, C.; Hofrichter, M. A.; Schroeder, J.; Schellens, R. T.; de Vrieze, E.; van Wijk, E.; Zechner, U.; Herms, S.; Hoffmann, P.; Mueller, T.; Dittrich, M.; Bartsch, O.; Krawitz, P. M.; Klopocki, E.; Shehata-Dieler, W.; Maroofian, R.; Wang, T.; Worley, P. F.; Goepfert, M. C.; Galehdari, H.; Lauer, A. M.; Haaf, T.; Vona, B.
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Abstract Background Understanding the phenotypic spectrum of disease-associated genes is essential for accurate diagnosis and targeted therapy. FRMPD4 (FERM and PDZ Domain Containing 4) has previously been associated with intellectual disability and epilepsy. However, its potential role in non-syndromic hearing loss has not been explored. Methods We performed genetic analysis in two unrelated families presenting with non-syndromic sensorineural hearing loss, identifying maternally inherited missense variants in FRMPD4. Clinical phenotyping included audiological assessment and evaluation for neurodevelopmental involvement. Cross-species expression analyses were conducted in Drosophila, zebrafish, and mouse. Functional characterization included quantitative evaluation of sound-evoked responses in Drosophila nicht gut hoerend (ngh) mutants, assessment of neuronal development and acoustic startle responses in zebrafish loss of function models, and morphological cochlear analyses with auditory brainstem response measurements in knockout mice. Results Three affected males from two unrelated families presented with prelingual, bilaterally symmetrical sensorineural hearing loss, with confirmed congenital onset in one individual and no evidence of neurodevelopmental abnormalities. Cross-species analyses demonstrated evolutionarily conserved expression of FRMPD4 in auditory structures. In Drosophila, quantitative analysis of sound-evoked responses in ngh mutants revealed impaired auditory function. Zebrafish loss of function models exhibited reduced neuronal populations in the otic vesicle and posterior lateral line, abnormal neuromast development, and diminished acoustic startle responses. In mice, Frmpd4 knockout resulted in high-frequency hearing loss and cochlear abnormalities consistent with the human phenotype. Conclusions Our findings expand the phenotypic spectrum of FRMPD4 to include non-syndromic sensorineural hearing loss and establish its evolutionarily conserved role in auditory function. These results have direct implications for genetic diagnosis and variant interpretation in patients with hearing loss.
Townsley, R.; Andrews, J.; Srivastav, S.; Jangam, S.; Hannan, S.; Kanca, O.; Yamamoto, S.; Wangler, M. F.
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Neuroligin-3 (NLGN3) was first identified as a risk gene associated with autism spectrum disorder (ASD). The initial variant, p.R451C, associating NLGN3 with ASD has been heavily investigated, yet little is known about the functional consequences of other NLGN3 variants. Furthermore, while most of the identified variants are present in males with maternally inherited variants from unaffected mothers, several de novo variants were observed in females, suggesting a possible functional difference between de novo and maternally inherited variants. To address the functional consequences of NLGN3 variants in vivo, we generated transgenic Drosophila models corresponding to one de novo variant (p.R175W) identified in one female proband, and two maternally inherited variants (p.R451C and p.R597W) identified in male probands. In Drosophila, loss of the fly homolog, Nlg3, altered sleep patterns, synaptic architecture, and vesicle dynamics, which were rescued by the expression of the human NLGN3Ref allele. When comparing the variants, the de novo p.R175W variant and the maternally inherited p.R451C variant altered synapse morphology and sleep patterns, with minimal effects on vesicle dynamics, and the p.R597W variant altered sleep and vesicle dynamics with minimal impact on synapse morphology. Using overexpression models, human NLGN3Ref altered sleep patterns and synaptic morphology. Moreover, the p.R175W variant exacerbated sleep phenotypes, and the p.R175W and p.R451C variants exacerbated synapse morphology phenotypes. Together, our findings suggest that de novo NLGN3 variants identified in females are likely gain-of-function, while maternally inherited variants have mixed loss-and gain-of-function effects. Moreover, the location of the variants may contribute to the distinct functional differences we observed. Some NLGN3 variants disrupt synaptic development, while other variants alter synaptic function, suggesting that NLGN3 variants have differential effects. These functional differences may provide insight into the heterogeneity of individuals with ASD. Author SummaryAutism spectrum disorder (ASD) is a common neurodevelopmental disorder. Mutations in the Neuroligin-3 (NLGN3) gene are associated with ASD but very few of these mutations have been characterized in animal models. Most of these mutations affect male individuals who maternally inherited their genetic mutation; however, more rarely female individuals may present with a genetic mutation that was not identified in either of the parents. Here, we utilized the fruit fly model to investigate how three different mutations, one mutation identified in a female and two mutations identified in males, affect the flys behavior and synapse development. We identified altered sleep patterns in some of our mutants which is consistent with sleep disturbances being highly comorbid with ASD. Additionally, we identified alterations in synapse development and function which is consistent with the role of NLGN3 in synapse formation and maturation. Together, our findings support that NLGN3 is important for regulating the synapse and mutations in this gene can alter its function. However, different mutations can have differential effects. This demonstrates the need to assess multiple variants simultaneously because each variant may have distinct functional significances.
Martin, A.; Llanes-Cuesta, M. A.; Hartley, J. N.; Frosk, P.; Drogemoller, B. I.; Wright, G. E. B.
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IntroductionNeuromuscular disorders (NMDs) encompass a broad group of conditions that primarily affect the peripheral nervous system. They are often caused by genetic alterations that impair skeletal muscle function and result in debilitating symptoms. Obtaining an accurate molecular diagnosis remains a challenge, potentially because variants in genes that have yet to be identified as causal. We therefore used advanced computational methods to study the genetic architecture of NMDs and to identify key features that distinguish NMD genes from other genes in the broader genome. MethodsCurated genes implicated in NMDs (n = 639; GeneTable of NMDs) were obtained and merged with a comprehensive set of genomic features for human autosomal protein-coding genes. Machine-learning-based feature selection and ranking were performed using Boruta, along with complementary analytical approaches. These analyses were used to identify the most important genic features (n = 134, subcategories: gene complexity, genetic variation, expression patterns, and other general gene traits) for discriminating NMD genes from other genes in the genome ResultsNMD genes exhibit enriched expression in disease-relevant tissues, including skeletal muscle and heart. Additionally, compared with other protein-coding genes, these genes exhibit increased transcriptomic complexity (e.g., longer transcripts and more unique isoforms), contain more short tandem repeats, and show greater variation in conservation across model organisms. ConclusionsThis study identified several key genomic features that may distinguish NMD genes from the rest of the genome. This may enhance the identification of novel causal genes and could ultimately facilitate earlier diagnosis and medical management for affected individuals.
Kuchina, A.; Sherstyukova, D.; Borovikov, A.; Soloshenko, M.; Zernov, N.; Subbotin, D.; Dadali, E.; Sharkova, I.; Rudenskaya, G.; Kutsev, S.; Skoblov, M.; Murtazina, A.
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Background: Facioscapulohumeral muscular dystrophy (FSHD) is a common hereditary neuromuscular disorder. The Russian FSHD Patient Registry was established in 2019 following the development of a PCR-based method for genetic confirmation of the diagnosis. Results: The registry included 470 participants (51% male). Genetic confirmation was obtained for 76% (n=356), the remainder were included based on clinical and anamnestic data. Clinical assessment forms and patient-reported questionnaires were analyzed for 310 and 142 patients, respectively. D4Z4 repeat unit (RU) distribution showed patterns consistent with European cohorts, with a predominance of patients with 3 RUs. A moderate inverse correlation was found between RUs number and clinical severity scales. Periscapular weakness was the most common onset manifestation (46.8%), followed by facial weakness (31.6%) which was often unnoticed by patients. The mean age in the Russian cohort was 37.8 years (range 0-97), indicating a younger cohort compared to international data. A delta-adjusted cluster analysis (n=215) identified three distinct trajectories: a classic phenotype with onset before age 14 and early involvement of various muscle groups (n=177), and two clusters characterized by either facial or periscapular onset with slow progression. Conclusion: The Russian FSHD registry provides a comprehensive characterization of a large national cohort, revealing a predominance of patients with 3 D4Z4 repeats and a younger demographic profile compared to international data. Cluster analysis identified three heterogeneous disease trajectories, offering a framework for improved patient stratification.
Abbas, T.; Naznine, M.; Mykha, M.; Mancha, M.; Hardas, A.; Raharja, P. A. R.; Chowdhury, M. E. H.
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Hypospadias, a common congenital anomaly requiring surgical correction, has seen growing research in surgical techniques and outcomes. However, no comprehensive bibliometric or disruption-based analysis exists to map the fields evolution. This study uses bibliometrics and the Disruption Index (DI) to identify key transformational research in hypospadias. A systematic search of five databases (PubMed, Web of Science, ScienceDirect, Scopus, and Dimensions) from January 1990 to December 2023 was conducted, yielding 7,732 articles. After applying inclusion criteria, 200 studies were analyzed. Citation data and DI scores were calculated using OpenCitations. Spearmans rank test assessed correlations between DI and citation metrics. A subgroup analysis identified trends based on the latest hypospadias research priorities. The mean citation count was 72.3 (SD = 43.1) with a mean DI of 0.011 (SD = 0.17). Five studies, focusing on complications, analgesia, and surgical techniques, had the highest DI (1.0). A moderate positive correlation was found between DI and citation rate ({rho} = 0.405, p < 0.001). Subgroup analysis showed most research focused on surgical techniques (30.5%) and etiology (25.8%), while areas like surgical training (2.6%) and innovation (0%) were underrepresented. This study identifies critical gaps in hypospadias research. The DI reveals influential studies that redirect research trajectories. Future work should focus on innovation and translational research to accelerate advancements in hypospadias care.
Weyermuller, C.; Andary, J.; Soliman, D.; Gates, P.
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OBJECTIVES: Compare results of the Pediatric Outcomes Data Collection Instrument (PODCI) in children ages 2-18 years with cerebral palsy (CP) across all severity levels of the Gross Motor Function Classification System (GMFCS) with children in the General Population, confirming discriminant validity as a performance assessment tool and health-related quality of life (HRQOL) measure. METHODS: Cross-sectional study: single response PODCI proxy survey databases of 5238 children ages 2-18 years in GP and 2470 in the Population with CP were analyzed. Statistical methods included Analysis of Variance (ANOVA), Analysis of Covariance (ANCOVA), Linear Trend Test, and Standard Error Assessment. RESULTS: A statistically significant difference exists between PODCI subscales in General Population and Population with CP across age groups and GMFCS levels. Motor scales and Global Functioning increase with age in both populations and are inversely proportional to GMFCS level in the Population with CP. HRQOL measures decrease with age in both populations with Happiness decreasing more in the General Population than those with CP as age increases. CONCLUSIONS: PODCI demonstrates a statistically significant difference in motor performance and HRQOL in children ages 2-18, between the General Population and the population with CP. PODCI is a valid performance assessment tool for use in CP ages 2-18 across all GMFCS levels. KEYWORDS: Cerebral Palsy, General Population, PODCI, ICF, Performance
Lee, L.; Tang, A. F.; Asako, A.; Ning, S. F.; Reed, H. A.; Duncan, E.; Lugar, H. M.; Hoekel, J.; Marshall, B. A.; Hershey, T.; Urano, F.
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Wolfram syndrome is a rare autosomal recessive disorder caused by pathogenic variants in the WFS1 gene, characterized by early-onset diabetes mellitus, optic atrophy, sensorineural hearing loss, arginine vasopressin deficiency, and progressive neurodegeneration. The condition selectively affects pancreatic {beta} cells and neurons via chronic endoplasmic reticulum (ER) stress, and no proven disease-modifying therapy currently exists. Diabetes mellitus is typically the first manifestation, presenting at a mean age of 6 years as an insulin-dependent phenotype with preserved C-peptide and negative diabetes-related autoantibodies. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are well-established agents in the management of type 2 diabetes, augmenting glucose-dependent insulin secretion, suppressing glucagon, slowing gastric emptying, and promoting satiety. Preclinical evidence further suggests that GLP-1 RAs preserve {beta}-cell mass, attenuate ER stress, and confer neuroprotective effects, properties of particular therapeutic relevance to Wolfram syndrome. We conducted a retrospective cohort study of 84 participants with genetically confirmed Wolfram syndrome and insulin-dependent diabetes mellitus enrolled in the Washington University Wolfram Syndrome International Registry and Clinical Study. Clinical data were extracted from medical records; for participants concurrently enrolled in the Tracking Neurodegeneration in Early Wolfram Syndrome study, longitudinal data were obtained from that source as well. Thirty-five percent of eligible participants had received a GLP-1 RA at some point during follow-up. We characterize the prevalence of GLP-1 RA use, documented rationale for initiation, observed effects on glycemic control and visual outcomes, adverse effects, and reasons for discontinuation. No statistically significant changes in hemoglobin A1c (HbA1c) or body mass index (BMI) were observed. Visual acuity declined significantly at two years, consistent with expected disease progression. Gastrointestinal adverse effects were common and contributed to frequent discontinuation. These observational data provide important clinical context and a foundation for future prospective trials evaluating GLP-1 RAs as a potential disease-modifying strategy in Wolfram syndrome.
Polo Sanchez, M.; Lesmes, A. C.; Muni, N.; Vigneault, F.; Novak, R.
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Background: Rett Syndrome (RTT) is a severe neurodevelopmental disorder affecting approximately 1 in 10,000 live female births worldwide. The Rett Syndrome Behaviour Questionnaire (RSBQ), remains one of the most widely used standardized behavioral assessment tools for RTT. However, the RSBQ was originally validated only in British English, limiting its applicability for Spanish-speaking caregivers and clinical centers across Latin America and Spain. Objective: The primary aim of this study was to develop and validate the comprehension of the Spanish translation of the RSBQ to ensure cultural and linguistic equivalence, enhance data reliability, and facilitate earlier, more accurate clinical assessments among Spanish-speaking RTT populations. Methods: Surveys were administered in two phases to Spanish-speaking caregivers between November 2023 and September 2025. Phase I consisted of 12 guided survey administrations with participants being able to ask clarifying questions and offer linguistic modifications of RSBQ questions. Phase II consisted of independent online administration of the refined Spanish RSBQ and a retest at least 7 days later. Participants were recruited through direct outreach and supported virtually during questionnaire completion. Results: Following data cleaning and quality control, a total of 51 caregivers successfully completed both surveys. The Spanish RSBQ demonstrated high caregiver comprehension and strong engagement across multiple Latin American countries, including Argentina, Mexico, and Peru. Responses were highly correlated between test and retest timepoints, and no question showed biased response distributions. A slight effect of response interval on test-retest correlation was observed, potentially indicating the impact of natural disease progression confounding retest evaluation for long (>80 day) intervals; however this effect did not impact the overall linguistic validation results as analysis of only <21 day test-retest responders confirmed the findings. Conclusions: This linguistic validation study represents the first formal step toward the clinical validation of the Spanish RSBQ, enabling broader inclusion of Spanish-speaking populations in RTT research. The collaborative, bilingual data collection strategy proved both feasible and effective, paving the way for multinational trials and expanding therapeutic accessibility through localized, patient-centered innovation.
Hagen, L. A.; Svarverud, E.; Krastina, I.; MacKenzie, G.; Baraas, R. C.
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Purpose: To assess the repeatability of a prototype super acuity test chart for measuring visual acuity at 12.5 cm, and its ability to detect hyperopia in adolescents and young adults. Methods: Repeatability was estimated as within-subject standard deviation of three repeated super acuity measurements performed in 41 university students (19-26 years). Associations between super acuity and cycloplegic refractive errors, ocular biometry, distance visual acuity, accommodation, age, and sex were assessed in 119 high school students (16-18 years) using linear mixed-effects models. ROC curves and Youden index were used to estimate the best super acuity thresholds to detect rest hyperopia. Results: Mean super acuities in the university and high school cohorts were 0.14 {+/-} 0.13 and 0.12 {+/-} 0.11 logMAR, respectively. Repeatability was 0.031. Super acuity was poorer in those with uncorrected hyperopia [spherical equivalent refractive error (SER) [≥] 1.00 D] than the others [SER < 1.00 D; P = 0.039]. There were significant associations between poorer super acuity and more positive ametropia (SER; P = 0.026), poorer accommodation amplitude (P < 0.001), shorter axial length (P = 0.013), male sex (P < 0.001), and age (P = 0.037). Sensitivity and specificity for detecting hyperopia (SER [≥] 1.00 D) were 63.2% and 64.2%, respectively, at a super acuity threshold of 0.09 logMAR. Discussion: The super acuity prototype shows promise as a screening indicator for hyperopia. Further studies are needed to optimize the test and testing protocol, and to assess its ability to detect uncorrected hyperopia in children.
Kmiecik, M. J.; O'Brien, L.; Szpyhulsky, M.; Iodice, V.; Freeman, R.; Jordan, J.; Biaggioni, I.; Kaufmann, H.; Vickery, R.; Miller, A.; Saunders, E.; Rushton, E.; Valle, L.; Norcliffe-Kaufmann, L.
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BackgroundAlthough neurogenic orthostatic hypotension (nOH) is a common and debilitating feature of multiple system atrophy (MSA), little is known about the burden of symptoms in the real world. ObjectivesTo design and conduct a cross-sectional community-based research survey targeting patients with MSA, with and without nOH. MethodsWe recruited patients with MSA to complete an anonymous online survey covering three core themes: 1) timely diagnosis, 2) nOH pharmacotherapy and refractory symptoms, and 3) confidence in physician knowledge. Responses were grouped by pre-specified diagnostic certainty levels. Relationships between symptoms, function, and pharmacotherapy were assessed using univariate and multivariate methods. ResultsWe analyzed 259 respondents with a self-reported diagnosis of MSA (age: M=64.38, SD=8.09 years; 44% female). In total, 42% also had a diagnosis nOH; 40% had symptoms highly suspicious of nOH, but no diagnosis; and 21% reported having never had their blood pressure measured in the standing position at a clinical visit. Treatment with a pressor agent was independently associated with the presence of other symptoms of autonomic failure. Each additional nOH symptom reported increased the odds of requiring pharmacotherapy by 18%. Yet, despite anti-hypotensive medication use, 97% of patients reported limitations in their ability to bathe, cook, or arise from a chair/bed with 76% needing caregiver support for refractory nOH symptoms. ConclusionsThis cross-sectional representative sample shows nOH is underrecognized and undertreated in MSA patients, leading to substantial functional limitations. It is our hope that these findings are leveraged for planning future trials and advocating for better treatments.
Bylstra, Y.; Yeo Juann, M.; Teo, J. X.; Goh, J.; Choi, C.; Chan, S.; Song, C.; Chew Yin Goh, J.; Chai, N.; Lieviant, J. A.; Toh, H. J.; Chan, S. H.; Blythe, R.; Menezes, M.; Yang, C.; Hodgson, J.; Graves, N.; Sng, J.; Lim, W. W.; Law, H. Y.; Amor, D.; Baynam, G.; Chan, J. K.; Chan, Y. H.; Tan, P.; Ng, I.; Lim, W. K.; Jamuar, S. S.
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Background As part of Singapore's effort towards precision medicine tailored to Asian diversity, we describe the implementation of a nationwide reproductive carrier screening program. Using a customised 112-gene panel, incorporating population-specific recessive genetic diseases, we outline the overall program design, and initial efforts of community and stakeholder engagement, to inform culturally appropriate implementation. Methods Participants receive culturally tailored online education regarding our reproductive screening program and are provided results with genetic counselling and reproductive options. Community and stakeholder perspectives were assessed through questionnaires and consultations with religious leaders. Results Recruitment is nation-wide, and since initiation of our pilot phase in September 2024, 1,619 couples have registered interest, with 60% uptake of those deemed eligible. Among the 456 couples that have received results to date, four couples (0.9%) were identified to be at increased risk. Community questionnaire responses (n=1002), involving couples who participated in the program as well as the general public, indicated interest is high (59%) across the cohort but awareness, intent to participate and implications for reproductive options differed by sociodemographic factors such as ancestry and religion. Healthcare professional respondents (n=113) acknowledged carrier screening will be routine in medical care, but report limited confidence and resources. Engagement with religious leaders indicated support for the program. Conclusion These early program outcomes and community engagement are guiding the implementation of expanding population-based carrier screening in Singapore, contingent on addressing practical challenges through equitable outreach and professional training.
Cheng, N.; Lima, S.; Litovchick, L. L.; Dickinson, A. J. G.
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BackgroundPrecise control of DYRK1A dosage is essential for embryonic development, including craniofacial morphogenesis. While LZTS2 is among the most consistently identified DYRK1A-interacting proteins, its roles in embryonic development remain incompletely understood, and its potential contribution to craniofacial development has not been examined. Xenopus laevis was used to test the role of LZTS2 in craniofacial development and its functional relationship with DYRK1A. ResultsLzts2 and Dyrk1a showed overlapping expression during craniofacial development, with both proteins present in developing facial tissues. Knockdown of Lzts2 disrupted craniofacial morphogenesis and reduced expression of the neural crest-associated genes sox9 and pax3. These phenotypes closely resembled those caused by decreasing Dyrk1a function. Sub-phenotypic reductions of Lzts2 and Dyrk1a synergized to produce craniofacial defects, while partial reduction of Lzts2 attenuated aspects of the phenotype caused by Dyrk1a overexpression. Comparative analysis of human phenotypes associated with copy number gains of LZTS2 and DYRK1A revealed striking overlap, consistent with a potential functional interaction between these genes in humans. ConclusionsThese findings identify Lzts2 as a previously unrecognized regulator of craniofacial development and support a functional interaction with Dyrk1a during embryogenesis. Modulating LZTS2 or related regulatory partners may provide a strategy to selectively tune DYRK1A-dependent developmental pathways
Smith, C. M.; Houlgreave, M. S.; Asghar, M.; Francis, S. T.; Jackson, S. R.
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BackgroundTourette Syndrome (TS) is a neurodevelopmental movement disorder involving involuntary motor and vocal tics believed to be characterised by disordered neural inhibition. Cortical representations have previously been manipulated by disruptions in the inhibitory neurotransmitter {gamma}-aminobutyric acid (GABA). However, while facial tics are the most reported motor tic, it is unclear if facial sensorimotor representations differ in TS. MethodsSixteen individuals with Tourette Syndrome (TS) or chronic tic disorder and twenty typically developing (TD) control participants underwent 3-Tesla functional magnetic resonance imaging (fMRI). Blood-oxygenation level-dependent (BOLD) responses were measured during a block-design task comprising cued facial movements of common facial tics (blinking, grimacing and jaw clenching). Activations in bilateral pre- and post-central cortices and supplementary motor areas (SMA) were examined. Conjunction analyses identified voxels commonly and uniquely activated across movements within each group. ResultsBoth groups showed significant activations in the bilateral sensorimotor cortices and SMA in response to blink, grimace and jaw clench movements, with no significant between-group differences. Between-group similarities were lowest for unique blink maps. Common voxel maps also revealed low between-group similarity, with reduced sensorimotor activation and no shared SMA activation across movements in the TS group. ConclusionVoluntary facial sensorimotor representations do not differ between groups. However, low similarities between group unique blink maps may reflect greater prevalence of blinking tics in TS. Additionally, reduced overlap in sensorimotor activation and absent common SMA engagement across cued movements in the TS group may indicate altered motor integration or action initiation.
Hones, G. S.; Liao, X.-H.; Mahler, E. A.; Herrmann, P.; Eckstein, A.; Fuhrer, D.; Castillo, J. M.; Chiang, J.; Vincent, A. L.; Weiss, R. E.; Dumitrescu, A. M.; Refetoff, S.; Moeller, L. C.
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BackgroundHeterozygous c.283+1G>A and c.283G>A variants in the THRB gene, encoding for thyroid hormone receptor (TR){beta}1 and {beta}2, lead to autosomal dominant macular dystrophy (ADMD). We report the detailed clinical characterization of two first-degree relatives with ADMD, heterozygous for THRB c.283+1G>A, and an unrelated ADMD patient with a novel variant, c.283G>C. The genomic and molecular consequences of both variants were studied. MethodsgDNA and mRNA were obtained from leukocytes. Clinical characterization included biochemistry, bone density and body composition, ECG, echocardiography, ultrasound, audiometry and color-vision. In vitro assays investigated TR function and DNA binding. ResultsThe patients manifested no resistance to thyroid hormone beta (RTH{beta}) and had normal FT4 and TSH. Detailed studies in two patients showed no goiter, tachycardia, hypercholesterinemia or hepatic steatosis. Hearing was not impaired. Both had impaired color vision and reduced bone density. RT-PCR from all three patients revealed skipping of exon 4 exclusive to TR{beta}1, producing a deletion of 87 amino acids in the N-terminal domain (TR{beta}1{Delta}NTD). In vitro, DNA-binding affinity of TR{beta}1{Delta}NTD to DR4-TRE with or without RXR was comparable to TR{beta}1WT. Surprisingly, TR{beta}1{Delta}NTD was transcriptionally twice more active than TR{beta}1WT with a similar EC50 for T3, demonstrating gain-of-function of TR{beta}1{Delta}NTD. THRA expression in leukocytes was increased by 3-fold compared to unrelated controls and different from RTH{beta} patients. ConclusionThese THRB splice site variants produce TR{beta}1 exon 4 skipping, resulting in a gain-of-function mutant, TR{beta}1{Delta}NTD. This explains the dominant ADMD phenotype devoid of RTH{beta} and suggests a TR{beta}1 gain-of-function syndrome.
ahmed, a. K.; Rodaini, s.
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Background: Saudi Arabia bears a disproportionate burden of autosomal recessive genetic disorders, driven by consanguineous marriage rates of 50 to 58% and elevated carrier frequencies for conditions such as sickle cell disease (carrier rate up to 25%), betathalassemia (12%), and spinal muscular atrophy (6%). The existing premarital screening program screens for only two conditions. We developed SafeGene, a computational platform that expands predictive genetic screening to 50+ conditions using region specific population genetics. Methods: SafeGene integrates five risk calculation engines: (1) Mendelian inheritance models for AR, AD, XR, and XD conditions; (2) Hardy Weinberg equilibrium based carrier probability estimation using Saudi, Gulf, and global databases; (3) a six level consanguinity coefficient calculator (F = 0 to 1/8) with risk amplification multipliers; (4) multifactorial polygenic risk models for 12 complex diseases; and (5) maternal age dependent trisomy risk curves. Built using React.js, Node.js/Express, and MongoDB with bilingual Arabic/English support. Results: The platform encompasses 50 genetic conditions across 12 categories. Validation against published Saudi data demonstrated concordance with observed disease frequencies. Economic modeling projects that expanding screening could prevent 2,800 to 4,200 affected births annually, yielding savings of SAR 1.2 to 2.8 billion ($320 to 746 million USD) per year. Conclusions: SafeGene represents a scalable, evidence-based digital health solution for comprehensive genetic screening addressing the unique population genetics of consanguineous Gulf societies. The platform is protected under pending patent applications in South Africa (CIPC) and Saudi Arabia (SAIP).
Aravamuthan, B. R.; Bailes, A. F.; Baird, M.; Bjornson, K.; Bowen, I.; Bowman, A.; Boyer, E.; Gelineau-Morel, R.; Glader, L.; Gross, P.; Hall, S.; Hurvitz, E.; Kruer, M. C.; Larrew, T.; Marupudi, N.; McPhee, P.; Nichols, S.; Noritz, G.; Oleszek, J.; Ramsey, J.; Raskin, J.; Riordan, H.; Rocque, B.; Shah, M.; Shore, B.; Shrader, M. W.; Spence, D.; Stevenson, C.; Thomas, S. P.; Trost, J.; Wisniewski, S.
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Objective Cerebral palsy (CP) affects approximately 1 million Americans and 18 million individuals worldwide, yet contemporary US epidemiologic data remains limited. We aimed to use Cerebral Palsy Research Network (CPRN) clinical registry to describe demographics and clinical characteristics of individuals with CP across the US and determine associations with gross motor function and genetic etiology. Methods Registry subjects were included if they had clinician-confirmed CP and prospectively entered data for Gross Motor Function Classification System (GMFCS) Level, gestational age, genetic etiology, CP distribution, and tone/movement types. Logistic regression was used to determine which of these variables plus race, sex, ethnicity, and age were associated with GMFCS level and genetic etiology. Results A total of 9,756 children and adults with CP from 22 CPRN sites met inclusion criteria. Participants were predominantly White (73.0%), male (57.3%), non-Hispanic (87.8%), and younger than 18 years (73.7%). Most were classified as GMFCS levels I-III (55.6%), born preterm (52.8%), had spasticity (83.8%), and had quadriplegia (41.9%); 12.2% were identified as having a genetic etiology. Tone/movement types, CP distribution, and gestational age were significantly associated with both GMFCS level and genetic etiology (p<0.001). Compared to White individuals, Black individuals were more likely to have greater gross motor impairment (p<0.001). Conclusion In this large US cohort, clinical and demographic factors, including race, were associated with gross motor function and genetic etiology in CP. These findings highlight persistent disparities and demonstrate the value of a national clinical registry for informing prognostication, quality improvement efforts, and targeted genetic testing strategies.