The transcription factor ZEB2 is essential for early embryonic development. Using CRISPR/Cas9, we generated a ZEB2 deficient human iPSC cell line (KICRi002A-4), carrying a homozygous 790 bp deletion in ZEB2 that involves part of exon 5, intron 5 and part of exon 6. The deletion leads to markedly reduced levels of a truncated ZEB2 transcript.
View Article and Find Full Text PDFBackground: Microcephaly with early-onset seizures (MCSZ) is a neurodevelopmental disorder caused by pathogenic variants in the DNA strand break repair protein, polynucleotide kinase 3'-phosphatase (PNKP).
Methods: We have used whole genome sequencing and Sanger sequencing to identify disease-causing variants, followed by a minigene assay, Western blotting, alkaline comet assay, γH2AX, and ADP-ribose immunofluorescence.
Results: Here, we describe a patient with compound heterozygous variants in PNKP, including a missense variant in the DNA phosphatase domain (T323M) and a novel splice acceptor site variant within the DNA kinase domain that we show leads to exon skipping.
DNA methyltransferase type 1 (DNMT1) is a major enzyme involved in maintaining the methylation pattern after DNA replication. Mutations in DNMT1 have been associated with autosomal dominant cerebellar ataxia, deafness and narcolepsy (ADCA-DN). We used fibroblasts, induced pluripotent stem cells (iPSCs) and induced neurons (iNs) generated from patients with ADCA-DN and controls, to explore the epigenomic and transcriptomic effects of mutations in DNMT1.
View Article and Find Full Text PDFSpinocerebellar disorders are a vast group of rare neurogenetic conditions, generally characterized by overlapping clinical symptoms including progressive cerebellar ataxia, spastic paraparesis, cognitive deficiencies, skeletal/muscular and ocular abnormalities. The objective of the present study is to identify the underlying genetic causes of the rare spinocerebellar disorders in the Pakistani population. Herein, nine consanguineous families presenting different spinocerebellar phenotypes have been investigated using whole exome sequencing.
View Article and Find Full Text PDFIntroduction: Pelvic girdle pain during and after pregnancy is a major public health problem with significant daily problems for affected women and their families. There is now accumulating evidence that pregnancy-related pelvic girdle pain originates from the sacroiliac joints and the pubic symphysis as well as their extra-articular ligaments. However, the heritability of the disease remains to be determined.
View Article and Find Full Text PDFPurpose: Orthostatic hypotension is a common condition with heterogeneous and, in many cases, unclear underlying pathophysiology. Frequent symptoms are syncope and falls with a strong impact on daily life. A two-generation family with eight individuals segregating early-onset severe orthostatic hypotension with persistent tachycardia in upright position and repeated faints was identified.
View Article and Find Full Text PDFMowat-Wilson syndrome (MWS) is a severe neurodevelopmental disorder caused by heterozygous variants in the gene encoding transcription factor . Affected individuals present with structural brain abnormalities, speech delay and epilepsy. In mice, conditional loss of Zeb2 causes hippocampal degeneration, altered migration and differentiation of GABAergic interneurons, a heterogeneous population of mainly inhibitory neurons of importance for maintaining normal excitability.
View Article and Find Full Text PDFFibromyalgia (FM) is an idiopathic chronic disease characterized by widespread musculoskeletal pain, hyperalgesia and allodynia, often accompanied by fatigue, cognitive dysfunction and other symptoms. Autoimmunity and neuroinflammatory mechanisms have been suggested to play important roles in the pathophysiology of FM supported by recently identified interferon signatures in affected individuals. However, the contribution of different components in the immune system, such as the B-lymphocytes, in the progression to FM are yet unknown.
View Article and Find Full Text PDFPurpose: The rationale behind the SUDden cardiac Death in the Young (SUDDY) cohort was to provide a complete nationwide, high-quality platform with integrated multisource data, for clinical and genetic research on sudden cardiac death (SCD) in the young, with the ultimate goal to predict and prevent SCD.
Participants: The cohort contains all SCD victims <36 years, in Sweden during the period 2000-2010. We assigned five population-based controls per case, together with parents of cases and controls, in total 15 633 individuals.
Diamond−Blackfan anemia (DBA) is one of the inherited bone marrow failure syndromes marked by erythroid hypoplasia. Underlying variants in ribosomal protein (RP) genes account for 80% of cases, thereby classifying DBA as a ribosomopathy. In addition to RP genes, extremely rare variants in non-RP genes, including GATA1, the master transcription factor in erythropoiesis, have been reported in recent years in patients with a DBA-like phenotype.
View Article and Find Full Text PDFDravet syndrome is an early onset devastating epilepsy syndrome usually caused by heterozygous mutations in SCN1A. We generated a human iPSC line (UUIGPi015-A) from dermal fibroblasts of a patient with Dravet syndrome carrying a deletion on chromosome 2 encompassing SCN1A and 9 flanking genes. Characterization of the iPSC line confirmed expression of pluripotency markers, tri-lineage differentiation capacity and absence of exogenous reprogramming factors.
View Article and Find Full Text PDFInduced pluripotent stem cells (iPSCs) from patients are an attractive disease model to study tissues with poor accessibility such as the brain. Using this approach, we and others have shown that trisomy 21 results in genome-wide transcriptional dysregulations. The effects of loss of genes on chromosome 21 is much less characterized.
View Article and Find Full Text PDFHeterozygous variants in POLR2A, encoding the largest subunit of RNA polymerase II, cause severe neurodevelopmental and multisystem abnormalities in humans. Using CRISPR/Cas9 we generated the human iPSC line KICRi002A-5 with a heterozygous truncating 4 bp insertion in exon 5 of the POLR2A gene. Analysis using qRT-PCR confirmed reduced POLR2A mRNA in KICRi002A-5 vs.
View Article and Find Full Text PDFCombined measurements of mRNA and protein expression in single cells enable in-depth analysis of cellular states. We present SPARC, an approach that combines single-cell RNA-sequencing with proximity extension essays to simultaneously measure global mRNA and 89 intracellular proteins in individual cells. We show that mRNA expression fails to accurately reflect protein abundance at the time of measurement, although the direction of changes is in agreement during neuronal differentiation.
View Article and Find Full Text PDFNeurochondrin (NCDN) is a cytoplasmatic neural protein of importance for neural growth, glutamate receptor (mGluR) signaling, and synaptic plasticity. Conditional loss of Ncdn in mice neural tissue causes depressive-like behaviors, impaired spatial learning, and epileptic seizures. We report on NCDN missense variants in six affected individuals with variable degrees of developmental delay, intellectual disability (ID), and seizures.
View Article and Find Full Text PDFAvailability of numerous high-quality iPSC lines is needed to overcome donor-associated variability caused by genetic background effects. We generated two human iPSC lines from dermal fibroblasts of two healthy females using Sendai virus reprogramming. Quality assessment of the iPSC lines confirmed the expression of pluripotency markers, trilineage differentiation capacity and absence of exogenous expression of reprogramming factors.
View Article and Find Full Text PDFDown syndrome (DS) is caused by trisomy for chromosome 21 (T21). We generated two induced pluripotent stem cell (iPSC) lines from skin fibroblasts of two males with DS using Sendai virus delivery of OCT4, SOX2, KLF4, and c-MYC. Characterization of the two iPSC lines, UUIGPi013-A and UUIPGi014-A, showed that they are genetically stable with a 47,XY,+21 karyotype.
View Article and Find Full Text PDFBardet-Biedl syndrome (BBS) is a ciliopathy characterized by retinitis pigmentosa, obesity, polydactyly, cognitive impairment and renal failure. Pathogenic variants in 24 genes account for the molecular basis of >80% of cases. Toward saturated discovery of the mutational basis of the disorder, we carefully explored our cohorts and identified a hominid-specific SINE-R/VNTR/Alu type F (SVA-F) insertion in exon 13 of BBS1 in eight families.
View Article and Find Full Text PDFBi-allelic loss-of-function variants in genes that encode subunits of the adaptor protein complex 4 (AP-4) lead to prototypical yet poorly understood forms of childhood-onset and complex hereditary spastic paraplegia: SPG47 (AP4B1), SPG50 (AP4M1), SPG51 (AP4E1) and SPG52 (AP4S1). Here, we report a detailed cross-sectional analysis of clinical, imaging and molecular data of 156 patients from 101 families. Enrolled patients were of diverse ethnic backgrounds and covered a wide age range (1.
View Article and Find Full Text PDFDiamond-Blackfan Anemia (DBA) is a congenital pure red cell aplasia caused by heterozygous variants in ribosomal protein genes. The hematological features associated with DBA are highly variable and non-hematological abnormalities are common. We report herein on an affected mother and her daughter presenting with transfusion-dependent anemia.
View Article and Find Full Text PDFBackground: Oesophageal atresia (OA) is a life-threatening developmental defect characterized by a lost continuity between the upper and lower oesophagus. The most common form is a distal connection between the trachea and the oesophagus, i.e.
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