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European Journal of Human Genetics :... Jun 2024Pathogenic, largely truncating variants in the ETS2 repressor factor (ERF) gene, encoding a transcriptional regulator negatively controlling RAS-MAPK signaling, have...
Pathogenic, largely truncating variants in the ETS2 repressor factor (ERF) gene, encoding a transcriptional regulator negatively controlling RAS-MAPK signaling, have been associated with syndromic craniosynostosis involving various cranial sutures and Chitayat syndrome, an ultrarare condition with respiratory distress, skeletal anomalies, and facial dysmorphism. Recently, a single patient with craniosynostosis and a phenotype resembling Noonan syndrome (NS), the most common disorder among the RASopathies, was reported to carry a de novo loss-of-function variant in ERF. Here, we clinically profile 26 individuals from 15 unrelated families carrying different germline heterozygous variants in ERF and showing a phenotype reminiscent of NS. The majority of subjects presented with a variable degree of global developmental and/or language delay. Their shared facial features included absolute/relative macrocephaly, high forehead, hypertelorism, palpebral ptosis, wide nasal bridge, and low-set/posteriorly angulated ears. Stature was below the 3rd centile in two-third of the individuals, while no subject showed typical NS cardiac involvement. Notably, craniosynostosis was documented only in three unrelated individuals, while a dolichocephalic aspect of the skull in absence of any other evidence supporting a premature closing of sutures was observed in other 10 subjects. Unilateral Wilms tumor was diagnosed in one individual. Most cases were familial, indicating an overall low impact on fitness. Variants were nonsense and frameshift changes, supporting ERF haploinsufficiency. These findings provide evidence that heterozygous loss-of-function variants in ERF cause a "RASopathy" resembling NS with or without craniosynostosis, and allow a first dissection of the molecular circuits contributing to MAPK signaling pleiotropy.
PubMed: 38824261
DOI: 10.1038/s41431-024-01642-7 -
American Journal of Medical Genetics.... May 2024Pathogenic variants of polycomb repressive complex-2 (PRC2) subunits are associated with overgrowth syndromes and neurological diseases. EZH2 is a major component of...
Pathogenic variants of polycomb repressive complex-2 (PRC2) subunits are associated with overgrowth syndromes and neurological diseases. EZH2 is a major component of PRC2 and mediates the methylation of H3K27 trimethylation (H3K27me3). Germline variants of EZH2 have been identified as a cause of Weaver syndrome (WS), an overgrowth/intellectual disability (OGID) syndrome characterized by overgrowth, macrocephaly, accelerated bone age, intellectual disability (ID), and characteristic facial features. Germline variants of SUZ12 and EED, other components of PRC2, have also been reported in the WS or Weaver-like syndrome. EZH1 is a homolog of EZH2 that interchangeably associates with SUZ12 and EED. Recently, pathogenic variants of EZH1 have been reported in individuals with dominant and recessive neurodevelopmental disorders. We herein present sisters with biallelic loss-of-function variants of EZH1. They showed developmental delay, ID, and central precocious puberty, but not the features of WS or other OGID syndromes.
PubMed: 38814056
DOI: 10.1002/ajmg.a.63726 -
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 -
Taiwanese Journal of Obstetrics &... May 2024
Detection of digynic triploidy in a second-trimester fetus presenting syndactyly, relative macrocephaly, intrauterine growth restriction, cardiomegaly, pericardial effusion, Dandy-Walker malformation, double bubble sign and single umbilical artery on prenatal ultrasound and a false negative...
Topics: Humans; Female; Pregnancy; Ultrasonography, Prenatal; Pregnancy Trimester, Second; Pregnancy Trimester, First; Dandy-Walker Syndrome; Adult; Cardiomegaly; Fetal Growth Retardation; Pericardial Effusion; Megalencephaly; Single Umbilical Artery; Triploidy; Abnormalities, Multiple; False Negative Reactions; Noninvasive Prenatal Testing
PubMed: 38802216
DOI: 10.1016/j.tjog.2024.03.014 -
American Journal of Medical Genetics.... May 2024Osteopathia Striata with Cranial Sclerosis (OSCS) is a rare genetic condition primarily characterized by metaphyseal striations of long bones, bone sclerosis,...
Osteopathia Striata with Cranial Sclerosis (OSCS) is a rare genetic condition primarily characterized by metaphyseal striations of long bones, bone sclerosis, macrocephaly, and other congenital anomalies. It is caused by pathogenic variants in AMER1, a tumor suppressor and a WNT signaling repressor gene with key roles in tissue regeneration, neurodevelopment, tumorigenesis, and other developmental processes. While somatic AMER1 pathogenic variants have frequently been identified in several tumor types (e.g., Wilms tumor and colorectal cancer), whether OSCS (i.e., with AMER1 germline variants) is a tumor predisposition syndrome is not clear, with only nine cases reported with tumors. We here report the first case of neuroblastoma diagnosed in a male child with OSCS, review all previously reported tumors diagnosed in individuals with OSCS, and discuss potential tumorigenic mechanisms of AMER1. Our report adds to the accumulating evidence suggesting OSCS is a tumor predisposition condition, highlighting the importance of maintaining a high index of suspicion for the associated tumors when evaluating patients with OSCS. Importantly, Wilms tumor stands out as the most commonly observed tumor in OSCS patients, underscoring the need for regular surveillance.
PubMed: 38801192
DOI: 10.1002/ajmg.a.63709 -
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 -
Hormones (Athens, Greece) May 2024Silver-Russell syndrome 5 (SRS5) is characterized by asymmetric intrauterine growth restriction (IUGR), poor postnatal growth, macrocephaly at birth, and feeding...
Silver-Russell syndrome 5 (SRS5) is characterized by asymmetric intrauterine growth restriction (IUGR), poor postnatal growth, macrocephaly at birth, and feeding difficulties. Other possible features include triangular shaped face, prominent forehead, hypertelorism, epicanthus, micrognathia, brachydactyly, clinodactyly of the 5th finger, and syndactyly of the 2nd and 3rd toes. Pathogenic variants of the HMGA2 (high mobility group AT-hook 2) gene, on chromosome 12q14, which regulates the transcription of growth factor IGF2, have recently been associated with this syndrome. Herein, we present a 2.5-year-old boy with growth delay, SRS-like phenotype, and a variant of uncertain significance in the HMGA2 gene, which has not, to the best of our knowledge, been described to date in the medical literature. So far, 28 pathogenic variants of the HMGA2 gene in patients with clinical SRS phenotype have recently been reported. Therefore, HMGA2 gene testing should always be done in SRS patients who are found to be negative for the typical 11p15 (epi)mutations and matUPD7, while the mutations should also be added to growth retardation disorder panels.
PubMed: 38789914
DOI: 10.1007/s42000-024-00562-x -
Epileptic Disorders : International... May 2024Pathogenic variants in CACNA1E are associated with early-onset epileptic and developmental encephalopathy (DEE). Severe to profound global developmental delay,...
Pathogenic variants in CACNA1E are associated with early-onset epileptic and developmental encephalopathy (DEE). Severe to profound global developmental delay, early-onset refractory seizures, severe hypotonia, and macrocephaly are the main clinical features. Patients harboring the recurrent CACNA1E variant p.(Gly352Arg) typically present with the combination of early-onset DEE, dystonia/dyskinesia, and contractures. We describe a 2-year-and-11-month-old girl carrying the p.(Gly352Arg) CACNA1E variant. She has a severe DEE with very frequent drug-resistant seizures, profound hypotonia, and episodes of dystonia and dyskinesia. Long-term video-EEG-monitoring documented subsequent tonic asymmetric seizures during wakefulness and mild paroxysmal dyskinesias of the trunk out of sleep which were thought to be a movement disorder and instead turned out to be focal hyperkinetic seizures. This is the first documented description of the EEG findings in this disorder. Our report highlights a possible overlap between cortical and subcortical phenomena in CACNA1E-DEE. We also underline how a careful electro-clinical evaluation might be necessary for a correct discernment between the two disorders, playing a fundamental role in the clinical assessment and proper management of children with CACNA1E-DEE.
PubMed: 38780451
DOI: 10.1002/epd2.20242