0000000000187640
AUTHOR
Han G. Brunner
Mutation-specific pathophysiological mechanisms define different neurodevelopmental disorders associated with SATB1 dysfunction
AbstractWhereas large-scale statistical analyses can robustly identify disease-gene relationships, they do not accurately capture genotype-phenotype correlations or disease mechanisms. We use multiple lines of independent evidence to show that different variant types in a single gene,SATB1, cause clinically overlapping but distinct neurodevelopmental disorders. Clinical evaluation of 42 individuals carryingSATB1variants identified overt genotype-phenotype relationships, associated with different pathophysiological mechanisms, established by functional assays. Missense variants in the CUT1 and CUT2 DNA-binding domains result in stronger chromatin binding, increased transcriptional repression…
Mutations in the gene encoding the basal body protein RPGRIP1L, a nephrocystin-4 interactor, cause Joubert syndrome.
Peters, T.A./0000-0001-8443-5500; van Beersum, Sylvia E.C./0000-0002-4552-2908; Cremers, Frans/0000-0002-4954-5592; Roepman, Ronald/0000-0002-5178-8163 WOS: 000247619800019 PubMed: 17558407 Protein- protein interaction analyses have uncovered a ciliary and basal body protein network that, when disrupted, can result in nephronophthisis ( NPHP), Leber congenital amaurosis, Senior- Loken syndrome ( SLSN) or Joubert syndrome ( JBTS)(1-6). However, details of the molecular mechanisms underlying these disorders remain poorly understood. RPGRIP1- like protein ( RPGRIP1L) is a homolog of RPGRIP1 ( RPGR-interacting protein 1), a ciliary protein defective in Leber congenital amaurosis(7,8). We show t…
Baraitser-Winter cerebrofrontofacial syndrome : Delineation of the spectrum in 42 cases
International audience; Baraitser-Winter, Fryns-Aftimos and cerebrofrontofacial syndrome types 1 and 3 have recently been associated with heterozygous gain-of-function mutations in one of the two ubiquitous cytoplasmic actin-encoding genes ACTB and ACTG1 that encode beta- and gamma-actins. We present detailed phenotypic descriptions and neuroimaging on 36 patients analyzed by our group and six cases from the literature with a molecularly proven actinopathy (9 ACTG1 and 33 ACTB). The major clinical anomalies are striking dysmorphic facial features with hypertelorism, broad nose with large tip and prominent root, congenital non-myopathic ptosis, ridged metopic suture and arched eyebrows. Iris…
Brunner syndrome associated MAOA dysfunction in human dopaminergic neurons results in NMDAR hyperfunction and increased network activity
AbstractBackgroundMonoamine neurotransmitter abundance affects motor control, emotion, and cognitive function and is regulated by monoamine oxidases. Amongst these, monoamine oxidase A (MAOA) catalyzes the degradation of dopamine, norepinephrine, and serotonin into their inactive metabolites. Loss-of-function mutations in the X-linked MAOA gene cause Brunner syndrome, which is characterized by various forms of impulsivity, maladaptive externalizing behavior, and mild intellectual disability. Impaired MAOA activity in individuals with Brunner syndrome results in bioamine aberration, but it is currently unknown how this affects neuronal function.MethodsWe generated human induced pluripotent s…
No major role for periconceptional folic acid use and its interaction with theMTHFR C677Tpolymorphism in the etiology of congenital anorectal malformations
Background: Both genetic and nongenetic factors are suggested to be involved in the etiology of congenital anorectal malformations (ARM). Maternal periconceptional use of folic acid supplements were inconsistently suggested to play a role in the prevention of ARM. Therefore, we investigated independent associations and interactions of maternal periconceptional folic acid supplement use and the infant and maternal MTHFR (methylenetetrahydrofolate reductase) C677T polymorphisms with the risk of ARM and subgroups of ARM. Methods: A case-control study was conducted among 371 nonsyndromic ARM cases and 714 population-based controls born between 1990 and 2012 using maternal questionnaires and DNA…
Recurrent Mutations in the Basic Domain of TWIST2 Cause Ablepharon Macrostomia and Barber-Say Syndromes
Contains fulltext : 153827.pdf (Publisher’s version ) (Open Access) Ablepharon macrostomia syndrome (AMS) and Barber-Say syndrome (BSS) are rare congenital ectodermal dysplasias characterized by similar clinical features. To establish the genetic basis of AMS and BSS, we performed extensive clinical phenotyping, whole exome and candidate gene sequencing, and functional validations. We identified a recurrent de novo mutation in TWIST2 in seven independent AMS-affected families, as well as another recurrent de novo mutation affecting the same amino acid in ten independent BSS-affected families. Moreover, a genotype-phenotype correlation was observed, because the two syndromes differed based s…
De Novo and Inherited Pathogenic Variants in KDM3B Cause Intellectual Disability, Short Stature, and Facial Dysmorphism
Contains fulltext : 202646.pdf (Publisher’s version ) (Open Access) By using exome sequencing and a gene matching approach, we identified de novo and inherited pathogenic variants in KDM3B in 14 unrelated individuals and three affected parents with varying degrees of intellectual disability (ID) or developmental delay (DD) and short stature. The individuals share additional phenotypic features that include feeding difficulties in infancy, joint hypermobility, and characteristic facial features such as a wide mouth, a pointed chin, long ears, and a low columella. Notably, two individuals developed cancer, acute myeloid leukemia and Hodgkin lymphoma, in childhood. KDM3B encodes for a histone …
NBEA : developmental disease gene with early generalized epilepsy phenotypes
Abstract: NBEA is a candidate gene for autism, and de novo variants have been reported in neurodevelopmental disease (NDD) cohorts. However, NBEA has not been rigorously evaluated as a disease gene, and associated phenotypes have not been delineated. We identified 24 de novo NBEA variants in patients with NDD, establishing NBEA as an NDD gene. Most patients had epilepsy with onset in the first few years of life, often characterized by generalized seizure types, including myoclonic and atonic seizures. Our data show a broader phenotypic spectrum than previously described, including a myoclonic-astatic epilepsy-like phenotype in a subset of patients. Ann Neurol 2018;84:796-803
WNT Signaling Perturbations Underlie the Genetic Heterogeneity of Robinow Syndrome
International audience; Locus heterogeneity characterizes a variety of skeletal dysplasias often due to interacting or overlapping signaling pathways. Robinow syndrome is a skeletal disorder historically refractory to molecular diagnosis, potentially stemming from substantial genetic heterogeneity. All current known pathogenic variants reside in genes within the noncanonical Wnt signaling pathway including ROR2, WNT5A, and more recently, DVL1 and DVL3. However, ∼70% of autosomal-dominant Robinow syndrome cases remain molecularly unsolved. To investigate this missing heritability, we recruited 21 families with at least one family member clinically diagnosed with Robinow or Robinow-like pheno…
Exome chip association study excluded the involvement of rare coding variants with large effect sizes in the etiology of anorectal malformations
IntroductionAnorectal malformations (ARM) are rare congenital malformations, resulting from disturbed hindgut development. A genetic etiology has been suggested, but evidence for the involvement of specific genes is scarce. We evaluated the contribution of rare and low-frequency coding variants in ARM etiology, assuming a multifactorial model.MethodsWe analyzed 568 Caucasian ARM patients and 1,860 population-based controls using the Illumina Human Exome Beadchip array, which contains >240,000 rare and low-frequency coding variants. GenomeStudio clustering and calling was followed by re-calling of 'no-calls' using zCall for patients and controls simultaneously. Single variant and gene-bas…