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Journal of the Association of Genetic... 2024Ring chromosome 14 is a rarely observed chromosomal abnormality characterized by a circular, ring-like appearance in one or both copies of chromosome 14. Ring chromosome...
Ring chromosome 14 is a rarely observed chromosomal abnormality characterized by a circular, ring-like appearance in one or both copies of chromosome 14. Ring chromosome 14 syndrome (OMIM #616606) is marked by global developmental delays, drug-resistant epilepsy, microcephaly, and ocular abnormalities. To date, fewer than 100 cases of ring chromosome 14 syndrome have been described in the medical literature. We describe a case of ring chromosome 14 and its clinical presentation in a 10-year-old female, adding to the literature about this rare condition.
PubMed: 38824650
DOI: No ID Found -
Journal of Community Genetics Jun 2024Congenital anomalies (CA) encompass all morphological or functional alterations originating prenatally and present at birth. The prenatal diagnosis of these anomalies...
Prevalence of congenital anomalies and prenatal diagnosis by birth institution (public vs. non-public): indicators of inequality in access to elective termination of pregnancy for fetal anomalies.
Congenital anomalies (CA) encompass all morphological or functional alterations originating prenatally and present at birth. The prenatal diagnosis of these anomalies can significantly impact the overall health of the pregnant individual and may influence her decision regarding the continuation of the pregnancy. In contexts where safe pregnancy termination is not guaranteed by the state, it can lead to unsafe procedures with severe consequences. In our research, we analyzed epidemiological information on CA to develop potential indicators of inequity in access to safe abortion prior to the legalization of legal termination of pregnancy in Argentina. We included cases from 13 public hospitals and 9 non-public subsector hospitals, from the period 2013-2020. Two groups of specific CA were selected: 1) CA capable of being prenatally diagnosed, and 2) CA related to vascular disruptive events. 10/18 of the selected CA capable of being prenatally diagnosed had a significantly higher prevalence in public hospitals (anencephaly, encephalocele, spina bifida, microcephaly, hydrocephalus, holoprosencephaly, hydranencephaly, diaphragmatic hernia, gastroschisis, bilateral renal agenesis). Non public hospitals had higher prenatal detection. Birth prevalence of CA related with vascular disruptive events (limb reduction, Moebius syndrome, amniotic band sequence) were significantly higher in public hospitals. These results suggest disparities in access to prenatal diagnosis and safe abortion based on socioeconomic status. There was a significant gap in access to prenatal diagnosis for CA and possibly to safe elective abortion depending on the type of institution (public vs. non-public).
PubMed: 38822971
DOI: 10.1007/s12687-024-00714-x -
American Journal of Medical Genetics.... Jun 2024N-acetyl-d-neuraminic acid synthase-congenital disorder of glycosylation (NANS-CDG) is a rare autosomal recessive defect in the N-acetyl-neuraminic acid biosynthesis...
N-acetyl-d-neuraminic acid synthase-congenital disorder of glycosylation (NANS-CDG) is a rare autosomal recessive defect in the N-acetyl-neuraminic acid biosynthesis pathway. Herein, we report the first Korean NANS-CDG patient. A 10-year-old boy was referred to our clinic because of incidental radiographic findings indicating spondyloepimetaphyseal dysplasia. The patient had microcephaly, cavum septum pellucidum, and ventriculomegaly at birth, and at 10 years, a very short stature. He had a history of idiopathic chronic immune thrombocytopenia, central adrenal insufficiency, and hypothyroidism since infancy. The first unprovoked seizure occurred at the age of 2 years, and he was subsequently admitted to the hospital frequently because of respiratory infections and intractable seizures. Exome sequencing identified unreported biallelic variants of the NANS gene. Clinical and genetic confirmation of NANS-CDG highlights its expanding phenotypic and genotypic diversity.
PubMed: 38822623
DOI: 10.1002/ajmg.a.63721 -
Molecular Therapy : the Journal of the... May 2024Vagus nerve regulates viral infection and inflammation via the alpha 7 nicotinic acetylcholine receptor (α7 nAChR); however, the role of α7 nAChR in ZIKA virus (ZIKV)...
Vagus nerve regulates viral infection and inflammation via the alpha 7 nicotinic acetylcholine receptor (α7 nAChR); however, the role of α7 nAChR in ZIKA virus (ZIKV) infection, which can cause severe neurological diseases such as microcephaly and Guillain-Barré syndrome, remains unknown. Here, we first examined the role of α7 nAChR in ZIKV infection in vitro. A broad effect of α7 nAChR activation was identified in limiting ZIKV infection in multiple cell lines. Combined with transcriptomics analysis, we further demonstrated that α7 nAChR activation promoted autophagy and ferroptosis pathways to limit cellular ZIKV viral loads. Additionally, activation of α7 nAChR prevented ZIKV-induced p62 nucleus accumulation, which mediated an enhanced autophagy pathway. By regulating proteasome complex and an E3 ligase NEDD4, activation of α7 nAChR resulted in increased amount of cellular p62, which further enhanced the ferroptosis pathway to reduce ZIKV infection. Moreover, utilizing in vivo neonatal mouse models, we showed that α7 nAChR is essential in controlling the disease severity of ZIKV infection. Taken together, our findings identify an α7 nAChR-mediated effect that critically contributes to limiting ZIKV infection, and α7 nAChR activation offers a novel strategy for combating ZIKV infection and its complications.
PubMed: 38822526
DOI: 10.1016/j.ymthe.2024.05.037 -
Pediatric Radiology Jun 2024Viral infections in low-income countries such as Brazil pose a significant challenge for medical authorities, with epidemics such as Zika virus infection having lasting...
Viral infections in low-income countries such as Brazil pose a significant challenge for medical authorities, with epidemics such as Zika virus infection having lasting effects. The increase in microcephaly among newborns has prompted investigations into the association between Zika virus and this congenital syndrome. The severity and prevalence of microcephaly led to the declaration of national and international emergencies. Extensive research has been conducted to understand the teratogenic effects of Zika virus, particularly its impact on neural progenitor cells in the fetal brain. Various pre- and postnatal imaging techniques, such as ultrasound, magnetic resonance imaging (MRI), and postnatal computed tomography (CT), have played crucial roles in diagnosing and monitoring malformations linked to congenital Zika virus infection in the central nervous system (CNS). These modalities can detect brain parenchymal abnormalities, calcifications, cerebral atrophy, and callosal anomalies. Additionally, three-dimensional ultrasound and fetal MRI provide detailed anatomical images, while CT can identify calcifications that are not easily detected by other methods. Despite advancements in imaging, there are still unanswered questions and ongoing challenges in comprehending the long-term effects and developmental impairments in children affected by Zika virus. Radiologists continue to play a crucial role in diagnosing and assisting in the management of these cases.
PubMed: 38822063
DOI: 10.1007/s00247-024-05944-2 -
Nature Medicine May 2024Most people with intellectual disability (ID) do not receive a molecular diagnosis following genetic testing. To identify new etiologies of ID, we performed a genetic...
Most people with intellectual disability (ID) do not receive a molecular diagnosis following genetic testing. To identify new etiologies of ID, we performed a genetic association analysis comparing the burden of rare variants in 41,132 noncoding genes between 5,529 unrelated cases and 46,401 unrelated controls. RNU4-2, which encodes U4 small nuclear RNA, a critical component of the spliceosome, was the most strongly associated gene. We implicated de novo variants among 47 cases in two regions of RNU4-2 in the etiology of a syndrome characterized by ID, microcephaly, short stature, hypotonia, seizures and motor delay. We replicated this finding in three collections, bringing the number of unrelated cases to 73. Analysis of national genomic diagnostic data showed RNU4-2 to be a more common etiological gene for neurodevelopmental abnormality than any previously reported autosomal gene. Our findings add to the growing evidence of spliceosome dysfunction in the etiologies of neurological disorders.
PubMed: 38821540
DOI: 10.1038/s41591-024-03085-5 -
Zhonghua Yi Xue Yi Chuan Xue Za Zhi =... Jun 2024Structural maintenance of chromosomes (SMC), including cohesin, condensin and the SMC5/6 complex, are protein complexes which maintain the higher structure and dynamic... (Review)
Review
Structural maintenance of chromosomes (SMC), including cohesin, condensin and the SMC5/6 complex, are protein complexes which maintain the higher structure and dynamic stability of chromatin. Such circular complexes, with similar structures, play pivotal roles in chromatid cohesion, chromosomal condensation, DNA replication and repair, as well as gene transcription. Despite extensive research on the functions of the SMCs, our understanding of the SMC5/6 complex has remained limited compared with the other two complexes. This article has reviewed the architecture and crucial physiological roles of the SMCs, and explored the associated phenotypes resulting from mutations of the SMC components such as Cornelia de Lange syndrome (CdLS) and microcephaly, with an aim to provide insights into their functions in eukaryotic cells and implications for human diseases.
Topics: Humans; Chromosomal Proteins, Non-Histone; Cell Cycle Proteins; Cohesins; Multiprotein Complexes; DNA-Binding Proteins; Adenosine Triphosphatases; Animals; De Lange Syndrome; Mutation
PubMed: 38818566
DOI: 10.3760/cma.j.cn511374-20231120-00262 -
Zhonghua Yi Xue Yi Chuan Xue Za Zhi =... Jun 2024To investigate the clinical features and genetic variant of a child with West syndrome due to a variant of NEXMIF gene.
OBJECTIVE
To investigate the clinical features and genetic variant of a child with West syndrome due to a variant of NEXMIF gene.
METHODS
A child who was admitted to the First Medical Center of Chinese PLA General Hospital in March 2021 was selected as the study subject. Clinical data of the patient was collected. The child and his parents were subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing and pathogenicity analysis.
RESULTS
The child, a 4-month-old boy, had presented with spastic seizures with no obvious cause. Abnormal EEG, severe hypsarrhythmia, and multiple spastic seizures were discovered. Cranial MRI revealed widening of the extracerebral space at the top of the frontal lobe. Physical examination revealed that the child could not hold his head up, and could not respond to sounds or follow objects with his eyes. He also has microcephaly, with height < 1 s. The child was diagnosed with West syndrome at a local hospital, and was given prednisone orally for 3 months, with seizures under control. Topiramate tablets were taken orally for maintenance treatment, and he has been seizure-free for 7 months. DNA sequencing revealed that he has harbored a de novo nonsense variant of c.982_c.983delTT (p.L328Dfs*23) in the NEXMIF gene.
CONCLUSION
For children with West syndrome with severe developmental delay or even regression as the first symptoms, uncontrollable seizures and abnormal facial appearance, mutations of the NEXMIF gene should be suspected, and genetic testing can facilitate early diagnosis and treatment.
Topics: Humans; Male; Infant; Spasms, Infantile; Mutation; Exome Sequencing; Genetic Testing
PubMed: 38818558
DOI: 10.3760/cma.j.cn511374-20220511-00321 -
Heliyon May 2024Autosomal Recurrent Primary Microscopic (MCPH, OMIM: 251200) is a neurodevelopmental disorder that is characterized by a noticeable decrease in brain size, particularly...
Autosomal Recurrent Primary Microscopic (MCPH, OMIM: 251200) is a neurodevelopmental disorder that is characterized by a noticeable decrease in brain size, particularly in the cerebral cortex, but with a normal brain structure and a non-progressive intellectual disability. has been identified as the gene that triggers primary microcephaly (MCPH1,OMIM: 607117). Here we report a case of autosomal recessive primary microcephaly as caused by a novel variant in the gene. Head circumference was measured by Magnetic Resonance Imaging (MRI), while the Wechsler Intelligence Scale was used to evaluate the intelligence of the individual being tested. B-ultrasound was used to assess gonadal development, and semen routine was used to assess sperm status. The whole-exome sequencing (WES) was performed on the proband. Sanger sequencing was conducted on the parents of the proband to determine if the novel variant in the MCPH1 gene was present. The effect of the mutation on the splicing of was verified by minigene approach. It was observed that the proband had autosomal recessive primary microcephaly and azoospermatism. A novel splice-site homozygous mutation (c.233+2T > G) of the gene was identified, which inherited from his parents. Minigene approach confirmed that c.233+2T > G could affect the splicing of . Therefore, our findings contributed to the mutation spectrum of the gene and may be useful in the diagnosis and gene therapy of MCPH.
PubMed: 38818167
DOI: 10.1016/j.heliyon.2024.e30285 -
Cell Death & Disease May 2024CSMD1 (Cub and Sushi Multiple Domains 1) is a well-recognized regulator of the complement cascade, an important component of the innate immune response. CSMD1 is highly...
CSMD1 (Cub and Sushi Multiple Domains 1) is a well-recognized regulator of the complement cascade, an important component of the innate immune response. CSMD1 is highly expressed in the central nervous system (CNS) where emergent functions of the complement pathway modulate neural development and synaptic activity. While a genetic risk factor for neuropsychiatric disorders, the role of CSMD1 in neurodevelopmental disorders is unclear. Through international variant sharing, we identified inherited biallelic CSMD1 variants in eight individuals from six families of diverse ancestry who present with global developmental delay, intellectual disability, microcephaly, and polymicrogyria. We modeled CSMD1 loss-of-function (LOF) pathogenesis in early-stage forebrain organoids differentiated from CSMD1 knockout human embryonic stem cells (hESCs). We show that CSMD1 is necessary for neuroepithelial cytoarchitecture and synchronous differentiation. In summary, we identified a critical role for CSMD1 in brain development and biallelic CSMD1 variants as the molecular basis of a previously undefined neurodevelopmental disorder.
Topics: Humans; Intellectual Disability; Membrane Proteins; Female; Male; Neurodevelopmental Disorders; Alleles; Malformations of Cortical Development; Child; Child, Preschool; Cell Differentiation; Tumor Suppressor Proteins
PubMed: 38816421
DOI: 10.1038/s41419-024-06768-6