American Journal of Medical Genetics Part A最新文献

To enhance the diagnosis, management, and monitoring of Chinese children with chromosome 15q11-q13 duplication syndrome (dup15q) by analyzing their genetic and clinical characteristics. In this study, one Chinese prenatal case and 21 postnatal cases genetically diagnosed with dup15q syndrome underwent a detailed assessment of genetic and clinical characteristics. Most patients had normal prenatal (12/22, 54.5%) and neonatal (14/21, 66.7%) histories. Most symptoms were developmental delays (motor: 18/21, 85.7%; cognition: 13/21, 61.9%; language: 12/21, 57.1%). Other common features included autism spectrum disorder (ASD)-related behaviors (10/21, 47.6%) and seizures (7/21, 33.3%). Trisomy microduplications accounted for 54.5% (12/22), and tetrasomy microduplications accounted for 40.9% (9/22) of cases. We compared the phenotypic differences between the two groups using a composite score. One rare case of paternal duplication presented with early-onset obesity and tapered fingers resembling Prader-Willi syndrome (PWS). In addition, non-invasive prenatal testing (NIPT) detected int dup(15) in prenatal cases. Some patients with epilepsy were well controlled without anti-seizure drugs or monotherapy (3/7, 42.8%), while others had refractory epilepsy. Chinese children with dup15q exhibited high clinical heterogeneity, including multisystem developmental delays, ASD-related symptoms, and seizures. Phenotypic severity is influenced by multiple factors. NIPT may show positive findings, and chromosomal microarray analysis (CMA) combined with methylation analysis is important.

To investigate the correlation between genetic abnormalities and fetal genitourinary (GU) anomalies in Eastern China and to provide assistance for the clinical management of fetuses with different types of GU anomalies. Five hundred forty-five fetuses with GU anomalies were enrolled, undergoing karyotyping, copy number variation sequencing (CNV-seq) or chromosomal microarray analysis (CMA), and trio-exome sequencing (trio-ES), and received long-term follow-ups from 6 months to 7 years. The top five GU anomalies were hydronephrosis, renal agenesis, multicystic dysplastic kidney, genital cysts, and genital abnormalities. 4.77% (19/398) of chromosomal abnormalities were detected by karyotyping, and 39 CNVs were revealed in 354 cases by CNV-seq/CMA simultaneously, with 6.50% (23/354) of additional CNVs. Genetic abnormalities were more frequent in reproductive system anomalies, nonisolated, and multiple GU anomalies. Two of eight with pathogenic/likely pathogenic genes were additionally detected. Five hundred thirty-four pregnancy outcomes were obtained, including 418 (76.70%) live births with favorable outcomes, two (0.37%) intrauterine fetal deaths, and 114 (20.92%) terminations mainly due to genetic abnormalities or nonisolated anomalies. The fetuses with reproductive system anomalies, nonisolated, and multiple GU anomalies were associated with genetic abnormalities. Therefore, a closed-loop management strategy including "diagnosis-assessment-intervention-follow-up" should be provided for fetuses with GU anomalies from pregnancy to postpartum period.

Postzygotic mutations of the PIK3CA gene constitutively activate the PI3K/AKT/mTOR pathway in patients with PIK3CA-related overgrowth spectrum (PROS), causing congenital mosaic tissue overgrowth. We established primary fibroblast cells from a patient with a novel somatic frameshift mutation (c.3190_3191insA, [p.H1065fs]) in PIK3CA, in which PI3K/AKT/mTOR signaling is activated compared to control fibroblasts. We assessed the therapeutic effects of three compounds (BYL719, ARQ092, and rapamycin) on the PI3K/AKT/mTOR signaling pathway and cell growth. Notably, BYL719 is more effective at inhibiting the overactivation of all key signaling molecules in the pathway at lower concentrations in patient-derived fibroblasts, while showing no significant effect on control fibroblasts. The insertion frameshift mutation is not located within the five domains, but it is a gain-of-function PIK3CA mutation contributing to PROS development. The results further confirmed the obvious advantages of the compound in targeted therapy for PROS patients.

Rubinstein-Taybi syndrome is a rare genetic condition associated with a wide range of physical, cognitive, and developmental impairments, yet its gastrointestinal manifestations remain poorly characterized. Case reports and small series suggest a high prevalence of gastroesophageal reflux, constipation, dysphagia, and nutritional compromise, but no large cohort has examined these symptoms in detail. This study aimed to characterize gastrointestinal and nutritional comorbidities in children with Rubinstein-Taybi syndrome seen at a tertiary pediatric center between 2013 and 2023. Among 85 affected patients, 46 (54%) reported gastrointestinal symptoms, and 31 (66%) were evaluated in the Gastroenterology clinic. Symptoms frequently predated the genetic diagnosis. Constipation was most common, followed by reflux symptoms, dysphagia, vomiting, and feeding intolerance or poor weight gain. Most patients underwent at least one diagnostic evaluation, including upper gastrointestinal imaging, video swallow studies, or esophagogastroduodenoscopy. Nearly half required gastrostomy tube support, typically in later childhood, with subsequent improvements in weight and body mass index z-scores and successful transitions to partial or full oral intake in some cases. Oral-fed patients demonstrated modest growth improvement over shorter follow-up intervals. These findings highlight a substantial gastrointestinal disease burden in Rubinstein-Taybi syndrome and underscore the importance of early recognition and multidisciplinary management.

To investigate the molecular cause of choroideremia in two unrelated patients with no detectable mutations in the CHM gene. Two unrelated patients were examined by an ophthalmologist to obtain a clinical diagnosis. Patient and control cells were cultured and used as a source of DNA, RNA, and protein for analysis. Exonic regions of CHM were Sanger sequenced and copy number analysis was performed by multiplex ligation-dependent probe amplification. mRNA transcripts were analyzed by Sanger sequencing from synthesized cDNA. Protein expression was probed with western blot analysis. Suspecting an inversion, PCR in one case and inverse PCR in the second case were employed to locate the precise DNA breakpoints. Patient 1 and 2 were clinically diagnosed with choroideremia by experienced ophthalmologists. In both cases, sequencing of the promoter and coding regions of the CHM gene revealed no mutation and copy number analysis of the gene did not detect the presence of any large deletions or duplications. RNA obtained from the patient cells showed only a partial transcript in patient 1, and an abnormal CHM splice isoform in patient 2. The results from RNA and DNA analyses suggested that both patients' genomic DNA might contain an inversion mutation. In patient 1, a long-range PCR product amplified over two breakpoints confirmed an inversion event. This 6 kb inversion spanned from the 5'UTR to the first intron (NM_000390.4(CHM): c.[-836_-826del; 49 + 5526_49 + 5856del; -825_49 + 5525inv; insCGTCT].). In patient 2, inverse PCR revealed a different novel inversion of approximately 85 kb, spanning from intron 2 to intron 8 (NM_000390.4(CHM):c.116 + 6659_1166 + 20670inv). To detect these two inversions in future choroideremia samples, multiplex PCR assays were developed that produce distinct banding patterns that are diagnostic for these two mutations. We have identified inversion mutations in the CHM gene resulting in choroideremia. Though uncommon, inversions should be investigated as a possible cause of the disease in CHM patients, especially for those in whom no point mutations or copy number variants are found.

The inaugural ReNU Hope Conference and Scientific Symposium was held from July 23-25, 2025 in Long Island, New York. This historic conference brought together the researchers responsible for the groundbreaking discovery of RNU4-2/ReNU syndrome, families, scientists, clinicians, trainees, therapeutic developers, and industry leaders from around the world. The key themes that emerged included: (1) Early recognition and diagnosis of ReNU Syndrome, (2) optimizing clinical care for this complex condition, (3) the importance of the family experience, (4) a need to elucidate the underlying genetic mechanism, (5) a need for quality natural history data and validated endpoints, and (6) exploring approaches to therapeutic development. This summary provides a broad overview of the conference, highlights the key presentations and discussions, and delineates priorities moving forward.

3MC syndrome is a rare congenital malformation disorder caused by biallelic pathogenic variants in COLEC10, COLEC11, and MASP1. It is characterized by distinctive craniofacial anomalies, growth retardation, developmental delay, and variable systemic findings. Here, we report seven previously unreported patients with 3MC syndrome from five unrelated families. The cohort included five females and two males, aged 1-10 years. All patients exhibited characteristic craniofacial features, including hypertelorism, blepharoptosis, highly arched eyebrows, and epicanthus inversus. Cleft lip and/or palate were present in six patients, caudal appendage in four, congenital heart disease in two, hearing loss in four, and periumbilical anomalies in six. All patients showed neuromotor developmental delay. Molecular analysis identified novel pathogenic variants in COLEC10 in five patients and pathogenic alterations in MASP1 in two patients, including an exon-level deletion. These findings expand the clinical and molecular spectrum of 3MC syndrome and highlight the value of comprehensive molecular testing in its diagnosis.