genomic rearrangements in a 391 French bilateral periventricular nodular heterotopia cohort: prevalence and phenotypic correlations.

Background: loss of function manifests across a broad spectrum of phenotypes, ranging from severe prenatal onset to asymptomatic cases. Bilateral periventricular nodular heterotopia (BPNH) consistently occurs in affected individuals. This retrospective study involving French patients with BPNH evaluates the prevalence of gene dosage anomalies and investigates genotype-phenotype correlations in a large cohort of French patients with BPNH.

Transcriptome and acetylome profiling identify crucial steps of neuronal differentiation in Rubinstein-Taybi syndrome.

Rubinstein-Taybi syndrome (RTS) is a rare and severe genetic developmental disorder characterized by multiple congenital anomalies and intellectual disability. CREBBP and EP300, the two genes known to cause RTS encode transcriptional coactivators with a catalytic lysine acetyltransferase (KAT) activity. Loss of CBP or p300 function results in a deficit in protein acetylation, in particular at histones.

Autosomal Dominant MPAN: Mosaicism Expands the Clinical Spectrum to Atypical Late-Onset Phenotypes.

Background: Mitochondrial membrane protein-associated neurodegeneration (MPAN) is caused by mutations in the C19orf12 gene. MPAN typically appears in the first two decades of life and presents with progressive dystonia-parkinsonism, lower motor neuron signs, optic atrophy, and abnormal iron deposits predominantly in the basal ganglia. MPAN, initially considered as a strictly autosomal recessive disease (AR), turned out to be also dominantly inherited (AD).

CBP-HSF2 structural and functional interplay in Rubinstein-Taybi neurodevelopmental disorder.

Patients carrying autosomal dominant mutations in the histone/lysine acetyl transferases CBP or EP300 develop a neurodevelopmental disorder: Rubinstein-Taybi syndrome (RSTS). The biological pathways underlying these neurodevelopmental defects remain elusive. Here, we unravel the contribution of a stress-responsive pathway to RSTS.

Cardiovascular and connective tissue disorder features in FLNA-related PVNH patients: progress towards a refined delineation of this syndrome.

Background: FLNA Loss-of-Function (LoF) causes periventricular nodular heterotopia type 1 (PVNH1), an acknowledged cause of seizures of various types. Neurological symptoms are inconstant, and cardiovascular (CV) defects or connective tissue disorders (CTD) have regularly been associated. We aimed at refining the description of CV and CTD features in patients with FLNA LoF and depicting the multisystemic nature of this condition.

Clinical description and mutational profile of a Moroccan series of patients with Rubinstein Taybi syndrome.

Background: Rubinstein-Taybi syndrome (RSTS; OMIM 180849) is a rare autosomal dominant developmental disorder with an estimated prevalence of one case per 125,000 live births. RSTS is characterized by typical face, broad thumbs and halluces, short stature, and intellectual disability. Facial dysmorphy is characteristic with microcephaly, low frontal hairline, arched eyebrows, long eyelashes, convex profile of nose, narrow palate, and micrognathia.

Rubinstein-Taybi Syndrome: A Model of Epigenetic Disorder.

The Rubinstein-Taybi syndrome (RSTS) is a rare congenital developmental disorder characterized by a typical facial dysmorphism, distal limb abnormalities, intellectual disability, and many additional phenotypical features. It occurs at between 1/100,000 and 1/125,000 births. Two genes are currently known to cause RSTS, and mutated in around 55% and 8% of clinically diagnosed cases, respectively.

Triple diagnosis of Wiedemann-Steiner, Waardenburg and DLG3-related intellectual disability association found by WES: A case report.

Background: The development of whole-exome sequencing (WES) and whole-genome sequencing (WGS) for clinical purposes now allows the identification of multiple pathogenic variants in patients with a rare disease. This occurs even when a single causative gene was initially suspected. We report the case of an 8-year-old patient with global developmental delays and dysmorphic features, with a possibly pathogenic variant in three distinct genes.

Evaluation of DNA Methylation Episignatures for Diagnosis and Phenotype Correlations in 42 Mendelian Neurodevelopmental Disorders.

Genetic syndromes frequently present with overlapping clinical features and inconclusive or ambiguous genetic findings which can confound accurate diagnosis and clinical management. An expanding number of genetic syndromes have been shown to have unique genomic DNA methylation patterns (called "episignatures"). Peripheral blood episignatures can be used for diagnostic testing as well as for the interpretation of ambiguous genetic test results.

PADDAS syndrome associated with hair dysplasia caused by a de novo missense variant of PUM1.

PUM1 has been very recently reported as responsible for a new form of developmental disorder named PADDAS syndrome. We describe here an additional patient with early onset developmental delay, epilepsy, microcephaly, and hair dysplasia, with a de novo heterozygous missense variant of PUM1: c.3439C > T, p.

Deletion in 2q35 excluding the IHH gene leads to fetal severe limb anomalies and suggests a disruption of chromatin architecture.

The organization of mammalian genomes into sub-megabase sized Topologically Associated Domains (TADs) has recently been revealed by techniques derived from Chromosome Conformation Capture (3 C), such as High Chromosome Contact map (Hi-C). Disruption of this organization by structural variations can lead to ectopic interactions between enhancers and promoters, and to alteration of genes expression patterns. This mechanism has already been described as the main pathophysiological mechanism in several syndromes with congenital malformations.

19p13 microduplications encompassing NFIX are responsible for intellectual disability, short stature and small head circumference.

Syndromes caused by copy number variations are described as reciprocal when they result from deletions or duplications of the same chromosomal region. When comparing the phenotypes of these syndromes, various clinical features could be described as reversed, probably due to the opposite effect of these imbalances on the expression of genes located at this locus. The NFIX gene codes for a transcription factor implicated in neurogenesis and chondrocyte differentiation.

Evaluation of Motor Skills in Children with Rubinstein-Taybi Syndrome.

Rubinstein-Taybi syndrome (RTS) is a rare genetic disease that associates intellectual disability with somatic characteristics. We have conducted a study of the overall motor abilities of RTS participants. Static postural performance as well as gait parameters were somewhat decreased, although not significantly compared to typically developing (TD) participants.