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Frontiers in Oncology 2024Somatic mutations in have been identified across various tumors, playing pivotal roles in tumorigenesis, tumor progression, and unfavorable prognoses. Despite its... (Review)
Review
Somatic mutations in have been identified across various tumors, playing pivotal roles in tumorigenesis, tumor progression, and unfavorable prognoses. Despite its established notoriety as an oncogenic driver, there is a growing interest in exploring the involvement of MYCN in human development. While variants have traditionally been associated with Feingold syndrome type 1, recent discoveries highlight gain-of-function variants, specifically p.(Thr58Met) and p.(Pro60Leu), as the cause for megalencephaly-polydactyly syndrome. The elucidation of cellular and murine analytical data from both loss-of-function (Feingold syndrome model) and gain-of-function models (megalencephaly-polydactyly syndrome model) is significantly contributing to a comprehensive understanding of the physiological role of MYCN in human development and pathogenesis. This review discusses the MYCN's functional implications for human development by reviewing the clinical characteristics of these distinct syndromes, Feingold syndrome, and megalencephaly-polydactyly syndrome, providing valuable insights into the understanding of pathophysiological backgrounds of other syndromes associated with the MYCN pathway and the overall comprehension of MYCN's role in human development.
PubMed: 38884091
DOI: 10.3389/fonc.2024.1417607 -
Molecular Genetics & Genomic Medicine Jun 2024Spinocerebellar ataxia 29 (SCA29) is a rare genetic disorder characterized by early-onset ataxia, gross motor delay, and infantile hypotonia, and is primarily associated...
BACKGROUND
Spinocerebellar ataxia 29 (SCA29) is a rare genetic disorder characterized by early-onset ataxia, gross motor delay, and infantile hypotonia, and is primarily associated with variants in the ITPR1 gene. Cases of SCA29 in Asia are rarely reported, limiting our understanding of this disease.
METHODS
A female Korean infant, demonstrating clinical features of SCA29, underwent evaluation and rehabilitation at our outpatient clinic from the age of 3 months to the current age of 4 years. Trio-based genome sequencing tests were performed on the patient and her biological parents.
RESULTS
The infant initially presented with macrocephaly, hypotonia, and nystagmus, with nonspecific findings on initial neuroimaging. Subsequent follow-up revealed gross motor delay, early onset ataxia, strabismus, and cognitive impairment. Further neuroimaging revealed atrophy of the cerebellum and vermis, and genetic analysis revealed a de novo pathogenic heterozygous c.800C>T, p.Thr267Met missense mutation in the ITPR1 gene (NM_001378452.1).
CONCLUSION
This is the first reported case of SCA29 in a Korean patient, expanding the genetic and phenotypic spectrum of ITPR1-related ataxias. Our case highlights the importance of recognizing early-onset ataxic symptoms, central hypotonia, and gross motor delays with poor ocular fixation, cognitive deficits, and isolated cerebellar atrophy as crucial clinical indicators of SCA29.
Topics: Humans; Female; Mutation, Missense; Inositol 1,4,5-Trisphosphate Receptors; Spinocerebellar Degenerations; Child, Preschool; Cerebellar Ataxia; Spinocerebellar Ataxias; Infant
PubMed: 38860480
DOI: 10.1002/mgg3.2466 -
Cureus May 2024Long-standing overt ventriculomegaly in adults (LOVA) is a kind of chronic hydrocephalus that has been reported to have started in infancy and is characterized by...
Long-standing overt ventriculomegaly in adults (LOVA) is a kind of chronic hydrocephalus that has been reported to have started in infancy and is characterized by severe ventriculomegaly and macrocephaly. It often manifests clinically in later adulthood. We describe the case of a 34-year-old male patient who had a history of chronic alcoholism and who had been complaining of headaches, disturbed gait, and frequent falls for three months when he arrived in a stupor at the emergency room. Massive ventriculomegaly with Evans' index of 0.40 was found during a head magnetic resonance imaging (MRI). The MRI results were more severe than the clinical manifestations. He was diagnosed with LOVA and treated with conservative hyperosmolar drugs, neuroprotective agents, and intravenous (IV) thiamine. The patient was discharged and consented to follow-up after a hospital stay of seven days.
PubMed: 38854239
DOI: 10.7759/cureus.59973 -
Frontiers in Genetics 2024Silver-Russell syndrome (SRS) is a clinically and genetically heterogeneous disorder. A retrospective analysis predicted that the live birth prevalence of SRS in Estonia...
Silver-Russell syndrome (SRS) is a clinically and genetically heterogeneous disorder. A retrospective analysis predicted that the live birth prevalence of SRS in Estonia is 1:15,886 [Yakoreva et al., Eur J Hum Genet, 2019, 27(11), 1649-1658]. The most common causative genetic mechanism in the proband is loss of paternal methylation in the imprinted control region 1 (ICR1) at 11p15.5 chromosome. A few studies suggested that inherited or loss-of-function alterations of the gene, including the whole-gene deletion and intragenic pathogenic variants, could cause a rare type of SRS. To date, less than 20 unrelated -related SRS cases have been reported, and the clinical information about these cases is limited. We report the first prenatal case of SRS with 8q12 deletion (including the gene). The fetus presented with intrauterine growth retardation, small for gestational age, relative macrocephaly at birth, and a protruding forehead. Unlike classical SRS cases, the fetus had micrognathia and did not show body asymmetry. We hope that the literature review in this study provides new insights into genotype-phenotype relationships of -related SRS.
PubMed: 38826801
DOI: 10.3389/fgene.2024.1387649 -
Revista de Neurologia Jun 2024Pathogenic variants in BRWD3 gene have been described as a rare cause of syndromic X-linked intellectual disability. Its phenotype shows neurodevelopmental delay with...
INTRODUCTION
Pathogenic variants in BRWD3 gene have been described as a rare cause of syndromic X-linked intellectual disability. Its phenotype shows neurodevelopmental delay with intellectual disability in all reported patients, facial dysmorphic features, macrocephaly, overgrowth and obesity. The great majority of cases yield point variants in the gene, only three large deletions including only the BRWD3 gene have been reported. The BRWD3 protein is an epigenetic reader that regulates chromatin remodeling. We report a boy with a compatible phenotype and a deletion including only this gene.
CASE REPORT
Boy, without family and perinatal pathological background, with neurodevelopmental delay: psychomotor delay, speech delay and intellectual disability, macrocephaly (p > 99) and obesity. Phenotype with facial dysmorphic features: wide forehead, deep set eyes, bulbous nose, prominent ears and pointed chin. The array-CGH analysis showed a 586 kb deletion at Xq21.1 including only one gene with associated disorder, BRWD3. Afterwards, the deletion was also identified in his asymptomatic mother and sister.
CONCLUSIONS
Our patient confirms that the haploinsufficiency due to BRWD3 deletion is a causal genetic mechanism of the BRWD3-related syndromic X-linked intellectual disability. It is important to recognize the phenotype for the diagnosis and follow up of the patients, and also to carry out the family genetic analysis in order to identify and give genetic counselling to the women who also have the genetic defect, because the majority of them are asymptomatic, as the mother and sister of our patient.
Topics: Humans; Megalencephaly; Male; Gene Deletion; Intellectual Disability; Mental Retardation, X-Linked; Phenotype; Child; Bromodomain Containing Proteins; Transcription Factors
PubMed: 38813790
DOI: 10.33588/rn.7811.2024057 -
Clinics and Practice May 2024Tatton-Brown-Rahman syndrome is a rare autosomal dominant hereditary disease caused by pathogenic variants in the gene, which is an important participant in epigenetic...
Tatton-Brown-Rahman syndrome is a rare autosomal dominant hereditary disease caused by pathogenic variants in the gene, which is an important participant in epigenetic regulation, especially during embryonic development, and is highly expressed in all tissues. The main features of the syndrome are high growth, macrocephaly, intellectual disability, and facial dysmorphic features. We present a clinical case of Tatton-Brown-Rahman syndrome in a ten-year-old boy with macrocephaly with learning difficulties, progressive eye impairment, and fatigue suspected by a deep learning-based diagnosis assistance system, Face2Gene. The proband underwent whole-exome sequencing, which revealed a recurrent nonsense variant in the 12th exon of the , leading to the formation of a premature stop codon-NM_022552.5:c.1443C>A (p.Tyr481Ter), in a heterozygous state. This variant was not found in parents, confirming its de novo status. The patient case described here contributes to the understanding of the clinical diversity of Tatton-Brown-Raman syndrome with a mild clinical presentation that expands the phenotypic spectrum of the syndrome. We report the first recurrent nonsense variant in the gene, suggesting a mutational hot-spot. Differential diagnoses of this syndrome with Sotos syndrome, Weaver syndrome, and Cowden syndrome, as well as molecular confirmation, are extremely important, since the presence of certain types of pathogenic variants in the gene significantly increases the risk of developing acute myeloid leukemia.
PubMed: 38804405
DOI: 10.3390/clinpract14030073 -
International Journal of Molecular... May 2024Macrocephaly, characterized by an abnormally large head circumference, often co-occurs with distinctive finger changes, presenting a diagnostic challenge for clinicians.... (Review)
Review
Macrocephaly, characterized by an abnormally large head circumference, often co-occurs with distinctive finger changes, presenting a diagnostic challenge for clinicians. This review aims to provide a current synthetic overview of the main acquired and genetic etiologies associated with macrocephaly and finger changes. The genetic cause encompasses several categories of diseases, including bone marrow expansion disorders, skeletal dysplasias, ciliopathies, inherited metabolic diseases, RASopathies, and overgrowth syndromes. Furthermore, autoimmune and autoinflammatory diseases are also explored for their potential involvement in macrocephaly and finger changes. The intricate genetic mechanisms involved in the formation of cranial bones and extremities are multifaceted. An excess in growth may stem from disruptions in the intricate interplays among the genetic, epigenetic, and hormonal factors that regulate human growth. Understanding the underlying cellular and molecular mechanisms is important for elucidating the developmental pathways and biological processes that contribute to the observed clinical phenotypes. The review provides a practical approach to delineate causes of macrocephaly and finger changes, facilitate differential diagnosis and guide for the appropriate etiological framework. Early recognition contributes to timely intervention and improved outcomes for affected individuals.
Topics: Humans; Megalencephaly; Fingers
PubMed: 38791606
DOI: 10.3390/ijms25105567 -
Genes Apr 2024Infantile onset transient hypomyelination (IOTH) is a rare form of leukodystrophy that is associated with transient motor impairment and delayed central nervous system...
Infantile onset transient hypomyelination (IOTH) is a rare form of leukodystrophy that is associated with transient motor impairment and delayed central nervous system myelination. Here, we report a case of a new mutation in the transmembrane protein 63A () gene identified using Whole-Exome Sequencing (WES) in an 8.5-year-old boy with clinical symptoms similar to IOTH. The patient exhibited a mild developmental delay, including hypotonia and delayed motor milestones, as well as some notable phenotypic characteristics, such as macrocephaly and macrosomia. Despite the absence of early neuroimaging, genetic testing revealed a paternally inherited variant in (NM_14698.3:c.220A>T;p:(Arg74*)), potentially linked to infantile transient hypomyelinating leukodystrophy type 19. Our findings in this study and the patient's favorable clinical course underscore the potential for successful myelination even with delayed initiation and may contribute to a better understanding of the genotype-phenotype correlation in IOTH, emphasizing the importance of genetic analysis in unresolved developmental delay cases and providing critical insights for accurate diagnosis, prognosis and potential therapeutic strategies in rare leukodystrophies.
Topics: Humans; Male; Membrane Proteins; Child; Codon, Nonsense; Exome Sequencing; Heterozygote; Hereditary Central Nervous System Demyelinating Diseases; Genetic Association Studies
PubMed: 38790154
DOI: 10.3390/genes15050525 -
PLoS Biology May 2024Autism spectrum disorders (ASD) frequently accompany macrocephaly, which often involves hydrocephalic enlargement of brain ventricles. Katnal2 is a...
Autism spectrum disorders (ASD) frequently accompany macrocephaly, which often involves hydrocephalic enlargement of brain ventricles. Katnal2 is a microtubule-regulatory protein strongly linked to ASD, but it remains unclear whether Katnal2 knockout (KO) in mice leads to microtubule- and ASD-related molecular, synaptic, brain, and behavioral phenotypes. We found that Katnal2-KO mice display ASD-like social communication deficits and age-dependent progressive ventricular enlargements. The latter involves increased length and beating frequency of motile cilia on ependymal cells lining ventricles. Katnal2-KO hippocampal neurons surrounded by enlarged lateral ventricles show progressive synaptic deficits that correlate with ASD-like transcriptomic changes involving synaptic gene down-regulation. Importantly, early postnatal Katnal2 re-expression prevents ciliary, ventricular, and behavioral phenotypes in Katnal2-KO adults, suggesting a causal relationship and a potential treatment. Therefore, Katnal2 negatively regulates ependymal ciliary function and its deletion in mice leads to ependymal ciliary hyperfunction and hydrocephalus accompanying ASD-related behavioral, synaptic, and transcriptomic changes.
Topics: Animals; Male; Mice; Autism Spectrum Disorder; Behavior, Animal; Cilia; Disease Models, Animal; Ependyma; Hippocampus; Hydrocephalus; Katanin; Mice, Inbred C57BL; Mice, Knockout; Neurons; Phenotype; Synapses; Transcriptome
PubMed: 38718086
DOI: 10.1371/journal.pbio.3002596