Publications by authors named "Bellus G"

Variation in the elastin gene (ELN) may contribute to connective tissue disease beyond the known disease associations of supravalvar aortic stenosis and cutis laxa. Exome data from MyCode Community Health Initiative participants were analyzed for ELN rare variants (mean allele frequency <1%, not currently annotated as benign). Participants with variants of interest underwent phenotyping by dual chart review using a standardized abstraction tool.

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  • A study analyzed rare variants in the elastin gene, linking them to connective tissue diseases beyond known conditions like Supravalvar Aortic Stenosis and Cutis Laxa.
  • Out of 184,293 participants in the MyCode Community Health Initiative, 296 had relevant gene variants, with 41% showing symptoms such as aortic hypoplasia and arterial dilation.
  • The research indicates that variations in the elastin gene are significantly associated with arterial dissection and may contribute to a broader spectrum of connective tissue disorders.
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The Rab family of guanosine triphosphatases (GTPases) includes key regulators of intracellular transport and membrane trafficking targeting specific steps in exocytic, endocytic, and recycling pathways. DENND5B (Rab6-interacting Protein 1B-like protein, R6IP1B) is the longest isoform of DENND5, an evolutionarily conserved DENN domain-containing guanine nucleotide exchange factor (GEF) that is highly expressed in the brain. Through exome sequencing and international matchmaking platforms, we identified five de novo variants in DENND5B in a cohort of five unrelated individuals with neurodevelopmental phenotypes featuring cognitive impairment, dysmorphism, abnormal behavior, variable epilepsy, white matter abnormalities, and cortical gyration defects.

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  • This study introduces 31 new individuals with 22 unique genetic variants related to SYN1 disorders, detailing the prevalence of symptoms like autism, epilepsy, and intellectual disability across these cases.
  • The research also identifies specific triggers for seizures, such as water contact and routine activities, and suggests that the type of genetic mutation can influence the severity of symptoms, particularly the relationship between early seizure onset and greater intellectual challenges.
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  • PARP6 is a neuronally enriched enzyme that plays a key role in the development and morphology of neurons, but its specific functions in the nervous system were not well understood until this study.
  • Researchers created a mouse model with a defective version of PARP6 using CRISPR-Cas9, which showed that while the mice did not have major developmental issues, they died shortly after birth, indicating the importance of PARP6's catalytic activity for survival after birth.
  • The study also found mutations in the PARP6 gene in human patients with various neurodevelopmental disorders, linking the loss of PARP6 function to problems in neuronal development and function, thereby highlighting its role as a crucial microtubule-regulating gene
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De novo pathogenic variants in (chromosome alignment maintaining phosphoprotein 1), which encodes kinetochore-microtubule associated protein on 13q34, cause a rare neurodevelopmental disorder. We enrolled 14 individuals with pathogenic variants in that were documented by exome sequencing or gene panel sequencing. Medical history interviews, seizure surveys, Vineland Adapted Behavior Scales Second Edition, and other behavioral surveys were completed by primary caregivers of available participants in Simons Searchlight.

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While most individuals with a clinical diagnosis of Neurofibromatosis type 1 (NF1) have a detectable pathogenic variant in the gene, other conditions have phenotypic features overlapping with NF1. Without molecular confirmation, individuals may be misdiagnosed and have a different underlying condition. Namely, if a child has constitutional mismatch repair deficiency (CMMRD), early detection and prevention strategies for cancer risk would include surveillance recommendations not typically recommended for children with NF1.

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Specific activating missense HRAS variants cause Costello syndrome (CS), a RASopathy with recognizable facial features. The majority of these dominant disease causing variants affect the glycine residues in position 12 or 13. A clinically suspected CS diagnosis can be confirmed through identification of a dominant pathogenic HRAS variant.

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Purpose: Deep phenotyping is an emerging trend in precision medicine for genetic disease. The shape of the face is affected in 30-40% of known genetic syndromes. Here, we determine whether syndromes can be diagnosed from 3D images of human faces.

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  • Frozen section is introduced as a new, efficient diagnostic method for pili trianguli et canaliculi, a hair condition.
  • This case series involved three young children with blonde hair that couldn't be styled properly.
  • The frozen section method allowed for clear visualization of hair shaft abnormalities under light microscopy, confirming the diagnosis.
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Lysine acetyltransferase 6A (KAT6A) and its paralog KAT6B form stoichiometric complexes with bromodomain- and PHD finger-containing protein 1 (BRPF1) for acetylation of histone H3 at lysine 23 (H3K23). We report that these complexes also catalyze H3K23 propionylation in vitro and in vivo. Immunofluorescence microscopy and ATAC-See revealed the association of this modification with active chromatin.

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  • A correction has been released for the article.
  • Both the PDF and HTML versions have been updated to reflect this correction.
  • Readers are encouraged to refer to the updated versions for accurate information.
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Purpose: Neurofibromatosis type 1 (NF1) is characterized by a highly variable clinical presentation, but almost all NF1-affected adults present with cutaneous and/or subcutaneous neurofibromas. Exceptions are individuals heterozygous for the NF1 in-frame deletion, c.2970_2972del (p.

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Background: Exon-targeted microarrays can detect small (<1000 bp) intragenic copy number variants (CNVs), including those that affect only a single exon. This genome-wide high-sensitivity approach increases the molecular diagnosis for conditions with known disease-associated genes, enables better genotype-phenotype correlations, and facilitates variant allele detection allowing novel disease gene discovery.

Methods: We retrospectively analyzed data from 63,127 patients referred for clinical chromosomal microarray analysis (CMA) at Baylor Genetics laboratories, including 46,755 individuals tested using exon-targeted arrays, from 2007 to 2017.

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  • * A study of 136 individuals with a specific mutation (p.Arg1809) revealed symptoms like multiple café-au-lait macules and developmental delays, with about a quarter showing Noonan-like features and more instances of short stature and pulmonic stenosis than typical NF1 patients.
  • * The research found that the p.Arg1809 mutation leads to issues in melanocytes that cause a unique pigmentary phenotype, highlighting the importance of this genotype-phenotype link for patient
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We report on a young girl with polysyndactyly, coarctation of the aorta, and tongue hamartomas. These features are similar to those reported in individuals with variant forms of orofaciodigital syndrome known as congenital heart defects, hamartomas of the tongue and polysyndactly (CHDHTP: OMIM 217085) [Örstavik et al., 1992] and orocardiodigital syndrome [Digilio et al.

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We report 24 unrelated individuals with deletions and 17 additional cases with duplications at 10q11.21q21.1 identified by chromosomal microarray analysis.

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Chiari malformations are multifactorial and heterogeneous entities, characterized by abnormalities in the posterior fossa. They have been identified in association with various genetic syndromes in recent years. Two previous studies have noted an association of Chiari malformations with Rubinstein-Taybi syndrome (RTS).

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Muir-Torre syndrome (MTS) is an autosomal dominant genodermatosis caused by mutations in the DNA mismatch repair genes MLH1 and MSH2. This case describes a patient with an extensive family history of colon cancer who experienced the onset of multiple sebaceous adenomas and carcinomas after undergoing kidney transplantation and receiving immunosuppressive therapy. The finding of deficient MSH2 expression in the immunohistochemical analysis of a sebaceous carcinoma prompted genetic testing for a systemic mutation in the mismatch repair gene.

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Legius syndrome, is a recently identified autosomal dominant disorder caused by loss of function mutations in the SPRED1 gene, with individuals mainly presenting with multiple café-au-lait macules (CALM), freckling and macrocephaly. So far, only SPRED1 point mutations have been identified as the cause of this syndrome. To determine if copy number changes (CNCs) are a cause of Legius syndrome, we have used a Multiplex Ligation-dependent Probe Amplification (MLPA) assay covering all SPRED1 exons in a cohort of 510 NF1-negative patients presenting with multiple CALMs with or without freckling, but no other NF1 diagnostic signs.

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Purpose: Mutations in the CDKL5 gene have been associated with an X-linked dominant early infantile epileptic encephalopathy-2. The clinical presentation is usually of severe encephalopathy with refractory seizures and Rett syndrome (RTT)-like phenotype. We attempted to assess the role of mosaic intragenic copy number variation in CDKL5.

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Supernumerary, derivative, and ring X chromosomes are relatively common in Turner syndrome females but have been reported rarely in males. To date, less than 10 cases have been published, of which only 2 have been partially characterized in defining the breakpoints and genetic content of the derivative X chromosome. We describe a male with mosaicism for a supernumerary X chromosome (46,XY/47,XY, r(X)) who has multiple congenital anomalies, including features of craniofrontonasal dysplasia (Mendelian Inheritance in Man 304110) and the presence of ectopic female reproductive organs.

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The limb-body wall complex (LBWC) is characterized by abdominal wall and limb defects, exstrophy of the cloaca (EC) by lack of closure of the lower abdominal wall and lack of cloacal septation, and the urorectal septum malformation sequence (URSMS) by absent perineal and anal openings, ambiguous genitalia, colonic, and renal anomalies. We report here on three fetuses whom have overlapping features of these disorders. Also we have reviewed the literature for cases with overlapping features of two or three of the above conditions.

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