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Genes May 2024Fragile X syndrome (FXS) is a genetic disorder caused by a mutation in the fragile X messenger ribonucleoprotein 1 () gene and known to be a leading cause of inherited... (Review)
Review
Fragile X syndrome (FXS) is a genetic disorder caused by a mutation in the fragile X messenger ribonucleoprotein 1 () gene and known to be a leading cause of inherited intellectual disability globally. It results in a range of intellectual, developmental, and behavioral problems. Fragile X premutation-associated conditions (FXPAC), caused by a smaller CGG expansion (55 to 200 CGG repeats) in the gene, are linked to other conditions that increase morbidity and mortality for affected persons. Limited research has been conducted on the burden, characteristics, diagnosis, and management of these conditions in Africa. This comprehensive review provides an overview of the current literature on FXS and FXPAC in Africa. The issues addressed include epidemiology, clinical features, discrimination against affected persons, limited awareness and research, and poor access to resources, including genetic services and treatment programs. This paper provides an in-depth analysis of the existing worldwide data for the diagnosis and treatment of fragile X disorders. This review will improve the understanding of FXS and FXPAC in Africa by incorporating existing knowledge, identifying research gaps, and potential topics for future research to enhance the well-being of individuals and families affected by FXS and FXPAC.
Topics: Fragile X Syndrome; Humans; Fragile X Mental Retardation Protein; Africa; Mutation; Trinucleotide Repeat Expansion
PubMed: 38927619
DOI: 10.3390/genes15060683 -
Genes May 2024Pathogenic variants in the gene lead to a spectrum of rare autosomal recessive phenotypes, including osteogenesis imperfecta (OI) Type XI, Bruck syndrome Type I (BS I),...
Pathogenic variants in the gene lead to a spectrum of rare autosomal recessive phenotypes, including osteogenesis imperfecta (OI) Type XI, Bruck syndrome Type I (BS I), and the congenital arthrogryposis-like phenotype (AG), each with variable clinical manifestations that are crucial for diagnosis. This study analyzed the clinical-genetic characteristics of patients with these conditions, focusing on both known and newly identified variants. We examined data from 15 patients, presenting symptoms of OI and joint contractures. Diagnostic methods included genealogical analysis, clinical assessments, radiography, whole exome sequencing, and direct automated Sanger sequencing. We diagnosed 15 patients with phenotypes due to biallelic variants-4 with OI Type XI, 10 with BS I, and 1 with the AG-like phenotype-demonstrating polymorphism in disease severity. Ten pathogenic variants were identified, including three novel ones, c.1373C>T (p.Pro458Leu), c.21del (p.Pro7fs), and c.831_832insCG (p.Gly278Argfs), and a recurrent variant, c.831dup (p.Gly278Argfs). Variant c.1490G>A (p.Trp497Ter) was found in two unrelated patients, causing OI XI in one and BS I in the other. Additionally, two unrelated patients with BS I and epidermolysis bullosa shared identical homozygous and variants. This observation illustrates the diversity of -related pathology and the importance of considering the full spectrum of phenotypes in clinical diagnostics.
Topics: Humans; Tacrolimus Binding Proteins; Male; Female; Arthrogryposis; Phenotype; Osteogenesis Imperfecta; Child; Child, Preschool; Pedigree; Exome Sequencing; Adolescent; Mutation; Infant; Adult; Nervous System Malformations
PubMed: 38927610
DOI: 10.3390/genes15060674 -
Genes May 2024Rubinstein-Taybi syndrome (RTS) is a rare genetic disorder characterized by intellectual disability, facial dysmorphisms, and enlarged thumbs and halluces. Approximately... (Review)
Review
Rubinstein-Taybi syndrome (RTS) is a rare genetic disorder characterized by intellectual disability, facial dysmorphisms, and enlarged thumbs and halluces. Approximately 55% of RTS cases result from pathogenic variants in the gene, with an additional 8% linked to the gene. Given the close relationship between these two genes and their involvement in epigenomic modulation, RTS is grouped into chromatinopathies. The extensive clinical heterogeneity observed in RTS, coupled with the growing number of disorders involving the epigenetic machinery, poses a challenge to a phenotype-based diagnostic approach for these conditions. Here, we describe the first case of a patient clinically diagnosed with RTS with a truncating variant in mosaic form. We also review previously described cases of mosaicism in and apply clinical diagnostic guidelines to these patients, confirming the good specificity of the consensus. Nonetheless, these reports raise questions about the potential underdiagnosis of milder cases of RTS. The application of a targeted phenotype-based approach, coupled with high-depth NGS, may enhance the diagnostic yield of whole-exome sequencing (WES) in mild and mosaic conditions.
Topics: Humans; CREB-Binding Protein; Mosaicism; Rubinstein-Taybi Syndrome; Phenotype; Mutation; Exome Sequencing; Male; Female
PubMed: 38927590
DOI: 10.3390/genes15060654 -
Genes May 2024To date, only 13 studies have described patients with large overlapping deletions of 10p11.2-p12. These individuals shared a common phenotype characterized by...
To date, only 13 studies have described patients with large overlapping deletions of 10p11.2-p12. These individuals shared a common phenotype characterized by intellectual disability, developmental delay, distinct facial dysmorphic features, abnormal behaviour, visual impairment, cardiac malformation, and cryptorchidism in males. Molecular cytogenetic analysis revealed that the deletion in this chromosomal region shares a common smallest region of overlap (SRO) of 80 kb, which contains only the gene (WW-domain-containing adaptor with coiled coil). In this clinical case report, we report a 5-year-old girl, born from non-consanguineous parents, with a 10p11.22p11.21 microdeletion. She presents clinical features that overlap with other patients described in the literature, such as dysmorphic traits, speech delay, and behavioural abnormalities (hyperactivity), even though the gene is not involved in the microdeletion. Our results are the first to highlight that the deletion described here represents a contiguous gene syndrome that is enough to explain the distinct phenotype but partially overlaps with the previous cases reported in the literature, even though the same genes are not involved. In particular, in this study, we speculate about the role of the gene that seems to be associated with normal motor development. In fact, we found that our patient is the only one described in the literature with a large deletion in the 10p11.22p11.21 region without the involvement of the gene deletion, and, interestingly, the patient did not have motor delay.
Topics: Humans; Female; Child, Preschool; Chromosome Deletion; Intellectual Disability; Abnormalities, Multiple; Syndrome; Phenotype; Developmental Disabilities
PubMed: 38927586
DOI: 10.3390/genes15060650 -
Biomedicines May 2024Alport syndrome is a hereditary disease caused by mutations in the genes encoding the alpha 3, alpha 4, and alpha 5 chains of type IV collagen. It is characterized by... (Review)
Review
Alport syndrome is a hereditary disease caused by mutations in the genes encoding the alpha 3, alpha 4, and alpha 5 chains of type IV collagen. It is characterized by hematuria, proteinuria, progressive renal dysfunction, hearing loss, and ocular abnormalities. The main network of type IV collagen in the glomerular basement membrane is composed of α3α4α5 heterotrimer. Mutations in these genes can lead to the replacement of this network by an immature network composed of the α1α1α2 heterotrimer. Unfortunately, this immature network is unable to provide normal physical support, resulting in hematuria, proteinuria, and progressive renal dysfunction. Current treatment options for Alport syndrome include angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, which aim to alleviate glomerular filtration pressure, reduce renal injury, and delay the progression of renal dysfunction. However, the effectiveness of these treatments is limited, highlighting the need for novel therapeutic strategies and medications to improve patient outcomes. Gene therapy, which involves the use of genetic material to prevent or treat diseases, holds promise for the treatment of Alport syndrome. This approach may involve the insertion or deletion of whole genes or gene fragments to restore or disrupt gene function or the editing of endogenous genes to correct genetic mutations and restore functional protein synthesis. Recombinant adeno-associated virus (rAAV) vectors have shown significant progress in kidney gene therapy, with several gene therapy drugs based on these vectors reaching clinical application. Despite the challenges posed by the structural characteristics of the kidney, the development of kidney gene therapy using rAAV vectors is making continuous progress. This article provides a review of the current achievements in gene therapy for Alport syndrome and discusses future research directions in this field.
PubMed: 38927366
DOI: 10.3390/biomedicines12061159 -
Biology Jun 2024Tumor cells display abnormal growth and division, avoiding the natural process of cell death. These cells can be benign (non-cancerous growth) or malignant (cancerous... (Review)
Review
Tumor cells display abnormal growth and division, avoiding the natural process of cell death. These cells can be benign (non-cancerous growth) or malignant (cancerous growth). Over the past few decades, numerous in vitro or in vivo tumor models have been employed to understand the molecular mechanisms associated with tumorigenesis in diverse regards. However, our comprehension of how non-tumor cells transform into tumor cells at molecular and cellular levels remains incomplete. The nematode has emerged as an excellent model organism for exploring various phenomena, including tumorigenesis. Although does not naturally develop cancer, it serves as a valuable platform for identifying oncogenes and the underlying mechanisms within a live organism. In this review, we describe three distinct germline tumor models in , highlighting their associated mechanisms and related regulators: (1) ectopic proliferation due to aberrant activation of GLP-1/Notch signaling, (2) meiotic entry failure resulting from the loss of GLD-1/STAR RNA-binding protein, (3) spermatogenic dedifferentiation caused by the loss of PUF-8/PUF RNA-binding protein. Each model requires the mutations of specific genes (, , and ) and operates through distinct molecular mechanisms. Despite these differences in the origins of tumorigenesis, the internal regulatory networks within each tumor model display shared features. Given the conservation of many of the regulators implicated in tumorigenesis, it is proposed that these unique models hold significant potential for enhancing our comprehension of the broader control mechanisms governing tumorigenesis.
PubMed: 38927305
DOI: 10.3390/biology13060425 -
Molecular Oncology Jun 2024Endometrioid ovarian cancers (EOvC) are usually managed as serous tumors. In this study, we conducted a comprehensive molecular investigation to uncover the distinct...
Endometrioid ovarian cancers (EOvC) are usually managed as serous tumors. In this study, we conducted a comprehensive molecular investigation to uncover the distinct biological characteristics of EOvC. This retrospective multicenter study involved patients from three European centers. We collected clinical data and formalin-fixed paraffin-embedded (FFPE) samples for analysis at the DNA level using panel-based next-generation sequencing and array-comparative genomic hybridization. Additionally, we examined mRNA expression using NanoString nCounter® and protein expression through tissue microarray. We compared EOvC with other ovarian subtypes and uterine endometrioid tumors. Furthermore, we assessed the impact of molecular alterations on patient outcomes, including progression-free survival (PFS) and overall survival (OS). Preliminary analysis of clinical data from 668 patients, including 86 (12.9%) EOvC, revealed more favorable prognosis for EOvC compared with serous ovarian carcinoma (5-year OS of 60% versus 45%; P = 0.001) driven by diagnosis at an earlier stage. Immunohistochemistry and copy number alteration (CNA) profiles of 43 cases with clinical data and FFPE samples available indicated that EOvC protein expression and CNA profiles were more similar to endometrioid endometrial tumors than to serous ovarian carcinomas. EOvC exhibited specific alterations, such as lower rates of PTEN loss, mutations in DNA repair genes, and P53 abnormalities. Survival analysis showed that patients with tumors harboring loss of PTEN expression had worse outcomes (median PFS 19.6 months vs. not reached; P = 0.034). Gene expression profile analysis confirmed that EOvC differed from serous tumors. However, comparison to other rare subtypes of ovarian cancer suggested that the EOvC transcriptomic profile was close to that of ovarian clear cell carcinoma. Downregulation of genes involved in the PI3K pathway and DNA methylation was observed in EOvC. In conclusion, EOvC represents a distinct biological entity and should be regarded as such in the development of specific clinical approaches.
PubMed: 38923749
DOI: 10.1002/1878-0261.13679 -
Molecular Genetics & Genomic Medicine Jun 2024To further comprehend the phenotype of multiple mitochondrial dysfunction syndrome type 3 (MMDS3:OMIM#615330) caused by IBA57 mutation. We present a case involving a...
OBJECTIVE
To further comprehend the phenotype of multiple mitochondrial dysfunction syndrome type 3 (MMDS3:OMIM#615330) caused by IBA57 mutation. We present a case involving a patient who experienced acute neurological regression, and the literature was reviewed.
METHODS
Clinical data and laboratory test results were collected; early language and development progress were tested; and genetic testing was performed. Bioinformatics analysis was performed using Mutation Taster and PolyPhen-2, and the literature in databases such as PubMed and CNKI was searched using MMDS3 and IBA57 as keywords.
RESULTS
The child, aged 1 year and 2 months, had motor decline, unable to sit alone, limited right arm movement, hypotonia, hyperreflexia of both knees, and Babinski sign positivity on the right side, accompanied by nystagmus. Blood lactate levels were elevated at 2.50 mmol/L. Brain MR indicated slight swelling in the bilateral frontoparietal and occipital white matter areas and the corpus callosum, with extensive abnormal signals on T1 and T2 images, along with the semioval center and occipital lobes bilaterally. The multiple abnormal signals in the brain suggested metabolic leukoencephalopathy. Whole-exome sequencing analysis revealed that the child had two heterozygous mutations in the IBA57 gene, c.286T>C (p.Y96H) (likely pathogenic, LP) and c.992T>A (p.L331Q) (variant of uncertain significance, VUS). As of March 2023, a literature search showed that 56 cases of MMDS3 caused by IBA57 mutation had been reported worldwide, with 35 cases reported in China. Among the 35 IBA57 mutations listed in the HGMD database, there were 28 missense or nonsense mutations, 2 splicing mutations, 2 small deletions, and 3 small insertions.
CONCLUSION
MMDS3 predominantly manifests in infancy, with primary symptoms including feeding difficulties, neurological functional regression, muscle weakness, with severe cases potentially leading to mortality. Diagnosis is supported by elevated lactate levels, multisystem impairment (including auditory and visual systems), and distinctive MRI findings. Whole-exome sequencing is crucial for diagnosis. Currently, cocktail therapy offers symptomatic relief.
Topics: Humans; Infant; Male; Phenotype; Mutation; Female; Microfilament Proteins; Carrier Proteins; Mitochondrial Diseases
PubMed: 38923322
DOI: 10.1002/mgg3.2485 -
Journal of Fungi (Basel, Switzerland) May 2024The acetylation of histone lysine residues regulates multiple life processes, including growth, conidiation, and pathogenicity in filamentous pathogenic fungi. However,...
The acetylation of histone lysine residues regulates multiple life processes, including growth, conidiation, and pathogenicity in filamentous pathogenic fungi. However, the specific function of each lysine residue at the N-terminus of histone H3 in phytopathogenic fungi remains unclear. In this study, we mutated the N-terminal lysine residues of histone H3 in , the main causal agent of Fusarium crown rot of wheat in China, which also produces deoxynivalenol (DON) toxins harmful to humans and animals. Our findings reveal that all the FpH3, FpH3, FpH3, and FpH3 mutants are vital for vegetative growth and conidiation. Additionally, FpH3K14 regulates the pathogen's sensitivity to various stresses and fungicides. Despite the slowed growth of the FpH3 and FpH3 mutants, their pathogenicity towards wheat stems and heads remains unchanged. However, the FpH3 mutant produces more DON. Furthermore, the FpH3 and FpH3 mutants exhibit significantly reduced virulence, with the FpH3 mutant producing minimal DON. In the FpH3, FpH3, FpH3, and FpH3 mutants, there are 1863, 1400, 1688, and 1806 downregulated genes, respectively, compared to the wild type. These downregulated genes include many that are crucial for growth, conidiation, pathogenicity, and DON production, as well as some essential genes. Gene ontology (GO) enrichment analysis indicates that genes downregulated in the FpH3 and FpH3 mutants are enriched for ribosome biogenesis, rRNA processing, and rRNA metabolic process. This suggests that the translation machinery is abnormal in the FpH3 and FpH3 mutants. Overall, our findings suggest that H3 N-terminal lysine residues are involved in regulating the expression of genes with important functions and are critical for fungal development and pathogenicity.
PubMed: 38921366
DOI: 10.3390/jof10060379 -
Clinics and Practice May 2024(1) Background: Sudden Infant Death Syndrome (SIDS) represents sudden and unexplained deaths during the sleep of infants under one year of age, despite thorough...
(1) Background: Sudden Infant Death Syndrome (SIDS) represents sudden and unexplained deaths during the sleep of infants under one year of age, despite thorough investigation. Screening for a prolonged QTc interval, a marker for Long QT Syndrome (LQTS), should be conducted on all newborns to reduce the incidence of SIDS. Neonatal electrocardiograms (ECGs) could identify congenital heart defects (CHDs) early, especially those not detected at birth. Infants with prolonged QTc intervals typically undergo genetic analysis for Long QT Syndrome. (2) Methods: The study involved infants aged 20-40 days, born with no apparent clinical signs of heart disease, with initial ECG screening. Infants with prenatal diagnoses or signs/symptoms of CHDs identified immediately after birth, as well as infants who had previously had an ECG or echocardiogram for other medical reasons, were excluded from the study. We used statistical software (SPSS version 22.0) to analyze the data. (3) Results: Of the 42,200 infants involved, 2245 were enrolled, with 39.9% being males. Following this initial screening, 164 children (37.8% males) with prolonged QTc intervals underwent further evaluation. Out of these 164 children, 27 children were confirmed to have LQTS. However, only 18 children were finally investigated for genetic mutations, and mutations were identified in 11 tests. The most common mutations were (54.5%), (36.4%), and (1 patient). Treatment options included propranolol (39.8%), nadolol (22.2%), inderal (11.1%), metoprolol (11.1%), and no treatment (16.7%). The most common abnormalities were focal right bundle branch block (54.5%), left axis deviation (9.2%), and nonspecific ventricular repolarization abnormalities (7.1%). Multiple anomalies were found in 0.47% of children with focal right bundle branch block. Structural abnormalities were associated with specific features in 267 patients (11.9%), primarily isolated patent foramen ovale (PFO) at 61.4%. (4) Conclusions: This screening approach has demonstrated effectiveness in the early identification of LQTS and other cardiac rhythm anomalies, with additional identification of mutations and/or prolonged QTc intervals in family members. Identifying other ECG abnormalities and congenital heart malformations further enhances the benefits of the screening.
PubMed: 38921260
DOI: 10.3390/clinpract14030082