-
PloS One 2019Mutations in EFTUD2 are responsible for the autosomal dominant syndrome named MFDM (mandibulofacial dysostosis with microcephaly). However, it is not clear how reduced...
Mutations in EFTUD2 are responsible for the autosomal dominant syndrome named MFDM (mandibulofacial dysostosis with microcephaly). However, it is not clear how reduced levels of EFTUD2 cause abnormalities associated with this syndrome. To determine if the mouse can serve as a model for uncovering the etiology of abnormalities found in MFDM patients, we used in situ hybridization to characterize expression of Eftud2 during mouse development, and used CRISPR/Cas9 to generate a mutant mouse line with deletion of exon 2 of the mouse gene. We found that Eftud2 was expressed throughout embryonic development, though its expression was enriched in the developing head and craniofacial regions. Additionally, Eftud2 heterozygous mutant embryos had reduced EFTUD2 mRNA and protein levels. Moreover, Eftud2 heterozygous embryos were born at the expected Mendelian frequency, and were viable and fertile despite being developmentally delayed. In contrast, Eftud2 homozygous mutant embryos were not found post-implantation but were present at the expected Mendelian frequency at embryonic day (E) 3.5. Furthermore, only wild-type and heterozygous E3.5 embryos survived ex vivo culture. Our data indicate that Eftud2 expression is enriched in the precusor of structures affected in MFDM patients and show that heterozygous mice carrying deletion of exon 2 do not model MFDM. In addition, we uncovered a requirement for normal levels of Eftud2 for survival of pre-implantation zygotes.
Topics: Abnormalities, Multiple; Animals; Embryo Implantation; Female; Humans; Loss of Function Mutation; Male; Mandibulofacial Dysostosis; Mice; Mice, Inbred C57BL; Microcephaly; Mutation; Peptide Elongation Factors; Phenotype; Pregnancy; Ribonucleoprotein, U5 Small Nuclear; Sequence Deletion
PubMed: 31276534
DOI: 10.1371/journal.pone.0219280 -
F1000Research 2019Lenz-Majewski syndrome (LMS) is characterized by osteosclerosis and hyperostosis of skull, vertebrae and tubular bones as well as craniofacial, dental, cutaneous, and...
Lenz-Majewski syndrome (LMS) is characterized by osteosclerosis and hyperostosis of skull, vertebrae and tubular bones as well as craniofacial, dental, cutaneous, and digit abnormalities. We previously found that LMS is caused by dominant missense mutations in the gene, which encodes phosphatidylserine synthase 1 (PSS1), an enzyme that catalyses the conversion of phosphatidylcholine to phosphatidylserine. The mutations causing LMS result in a gain-of-function, leading to increased enzyme activity and blocking end-product inhibition of PSS1. Here, we have used transpose-mediated transgenesis to attempt to stably express wild-type and mutant forms of human ubiquitously or specifically in chondrocytes, osteoblasts or osteoclasts in zebrafish. We report multiple genomic integration sites for each of 8 different transgenes. While we confirmed that the ubiquitously driven transgene constructs were functional in terms of driving gene expression following transient transfection in HeLa cells, and that all lines exhibited expression of a heart-specific cistron within the transgene, we failed to detect gene expression at either the RNA or protein levels in zebrafish. All wild-type and mutant transgenic lines of zebrafish exhibited mild scoliosis with variable incomplete penetrance which was never observed in non-transgenic animals. Collectively the data suggest that the transgenes are silenced, that animals with integrations that escape silencing are not viable, or that other technical factors prevent transgene expression. In conclusion, the incomplete penetrance of the phenotype and the lack of a matched transgenic control model precludes further meaningful investigations of these transgenic lines.
Topics: Animals; Animals, Genetically Modified; CDP-Diacylglycerol-Inositol 3-Phosphatidyltransferase; Cell Lineage; HeLa Cells; Humans; Nitrogenous Group Transferases; Short Rib-Polydactyly Syndrome; Transgenes; Zebrafish
PubMed: 31231513
DOI: 10.12688/f1000research.17314.1 -
Radiation Research Aug 2019Radiological exposure scenarios involving large numbers of people require a rapid and high-throughput method to identify the unexposed, and those exposed to low- and...
Radiological exposure scenarios involving large numbers of people require a rapid and high-throughput method to identify the unexposed, and those exposed to low- and high-dose radiation. Those with high-dose exposure, e.g., >2 Gy and depending on host characteristics, may develop severe hematological acute radiation syndrome (HARS), requiring hospitalization and treatment. Previously, we identified a set of genes that discriminated these clinically relevant groups. In the current work, we examined the utility of gene expression changes to classify 1,000 split blood samples into HARS severity scores of H0, H1 and H2-4, with the latter indicating likely hospitalization. In several previous radiation dose experiments, we determined that these HARS categories corresponded, respectively, to doses of 0 Gy (unexposed), 0.5 Gy and 5 Gy. The main purpose of this work was to assess the rapidity of blood sample processing using targeted next-generation sequencing (NGS). Peripheral blood samples from two healthy donors were X-ray irradiated and incubated at 37°C for 24 h. A total of 1,000 samples were evaluated by laboratory personnel blinded to the radiation dose. Changes in gene expression of , , and were examined with qRT-PCR as positive controls. Targeted NGS (TREX) was used on all samples for the same four genes. Agreement using both methods was almost 78%. Using NGS, all 1,000 samples were processed within 30 h. Classification of the HARS severity categories corresponding to radiation dose had an overall agreement ranging between 90-97%. Depending on the end point, either a combination of all genes or alone (H0 HARS or unexposed) provided the best classification. Using this optimized automated methodology, we assessed 100× more samples approximately three times faster compared to standard cytogenetic studies. We showed that a small set of genes, rather than a complex constellation of genes, provided robust positive (97%) and negative (97%) predictive values for HARS categories and radiation doses of 0, 0.5 and 5 Gy. The findings of this study support the potential utility of early radiation-induced gene expression changes for high-throughput biodosimetry and rapid identification of irradiated persons in need of hospitalization.
Topics: Acute Radiation Syndrome; Adult; False Positive Reactions; Female; Gene Expression Profiling; Humans; Male; Radiation Exposure; Time Factors; Triage; Young Adult
PubMed: 31211643
DOI: 10.1667/RR15360.1 -
BMJ Case Reports May 2019Microcephalic osteodysplastic primordial dwarfism syndrome II (MOPDII) is microcephalic primordial dwarfism and is a very rare form of disproportionate short stature....
Microcephalic osteodysplastic primordial dwarfism syndrome II (MOPDII) is microcephalic primordial dwarfism and is a very rare form of disproportionate short stature. This disorder shares common features with other forms of microcephalic primordial dwarfism, including severe prenatal and postnatal growth retardation with marked microcephaly. However, it includes characteristic skeletal dysplasia, abnormal dentition and increased risk for cerebrovascular diseases. Recent reports added more features, including café-au-lait lesions, cutis marmorata, astigmatism, Moyamoya disease, insulin resistance, obesity, abnormal skin pigmentation and acanthosis nigricans around the neck. Clearly, the more MOPDII reports that are produced, the more information will be added to the spectrum of MOPDII features that can improve our understanding of this disorder. In this paper, we reported a new case of MOPDII with more severe clinical features, earlier onset of common features, in addition to a homozygous novel variant in the gene.
Topics: Antigens; Consanguinity; Dwarfism; Feeding and Eating Disorders; Fetal Growth Retardation; Homozygote; Humans; Infant; Male; Microcephaly; Nervous System Diseases; Osteochondrodysplasias; Parenteral Nutrition; Rare Diseases
PubMed: 31151966
DOI: 10.1136/bcr-2018-224197 -
Gene May 2019Autosomal recessive disorder is closely correlated with congenital fetal malformation. The mutation of WDR35 may lead to short rib-polydactyly syndrome (SRP),...
BACKGROUND
Autosomal recessive disorder is closely correlated with congenital fetal malformation. The mutation of WDR35 may lead to short rib-polydactyly syndrome (SRP), asphyxiating thoracic dystrophy (ATD, Jeune syndrome) and Ellis van Creveld syndrome. The purpose of this study is to investigate the role of WDR35 in fetal anomaly.
RESULTS
The fetuses presented malformation with abnormal head shape, cardiac dilatation, pericardial effusion, and non-displayed left pulmonary artery and left lung. After the detection of genomic DNA (gDNA) in amniotic fluid cells (AFC), chromosomal rearrangement was found in arr[hg19] 2p25.3p23.3. It was revealed through multiple PCR-DHPLC that MYCN, WDR35, LPIN1, ODC1, KLF11 and NBAS contained duplicated copy numbers in 2p25.3p23.3. AF-MSCs were mostly positive for CD44, CD105, negative for CD34 and CD14. Western Blot test showed that WDR35-encoded protein was decreased in the patients' AFC compared to that in normal pregnant women. In the patients' amniotic fluid-derived mesenchymal stem cells (AF-MSCs), WDR35 overexpression could repair cilia formation, and the overexpression of WDR35 or Gli2 could significantly enhance ALP activity and expressions of osteogenic differentiation marker genes, including RUNXE2, OCN, BSP and ALP. However, WDR35 silencing in C3H10T1/2 cells could remarkably inhibit cilia formation and osteogenic differentiation. This inhibitory effect could be attenuated by Gli2 overexpression.
CONCLUSIONS
The results demonstrated that copy number variation (CNV) of WDR35 may lead to skeletal dysplasia and fetal anomaly, and that down-regulated WDR35 may damage the cilia formation and sequentially indirectly regulate Gli signal, which would eventually result in negative regulation of osteogenic differentiation.
Topics: Adult; Amniotic Fluid; Animals; Bone Diseases, Developmental; Cell Differentiation; Cilia; Cytoskeletal Proteins; DNA Copy Number Variations; Female; Fetal Development; Hedgehog Proteins; Humans; Intracellular Signaling Peptides and Proteins; Mesenchymal Stem Cells; Mice; Mice, Inbred C3H; Osteogenesis; Phenotype; Polymorphism, Single Nucleotide; Pregnancy; Proteins
PubMed: 30790652
DOI: 10.1016/j.gene.2019.02.034 -
American Journal of Medical Genetics.... Apr 2019We report novel causative mutations in the IFT80 gene identified in four fetuses from two unrelated families with Beemer-Langer syndrome (BLS) or BLS-like phenotypes. We...
We report novel causative mutations in the IFT80 gene identified in four fetuses from two unrelated families with Beemer-Langer syndrome (BLS) or BLS-like phenotypes. We discuss the implication of the IFT80 gene in ciliopathies, and its diagnostic value for BLS among other SRPS.
Topics: Carrier Proteins; Female; Fetus; Humans; Male; Mutation; Pedigree; Phenotype; Prenatal Diagnosis; Short Rib-Polydactyly Syndrome
PubMed: 30767363
DOI: 10.1002/ajmg.a.61050 -
Nature Genetics Jan 2019In the version of this article originally published, the main-text sentence "In three patients of European ancestry, we identified the germline variant encoding...
In the version of this article originally published, the main-text sentence "In three patients of European ancestry, we identified the germline variant encoding p.Ile97Met in TIM-3, which was homozygous in two (P12 and P13) and heterozygous in one (P15) in the germline but with no TIM-3 plasma membrane expression in the tumor" misstated the identifiers of the two homozygous individuals, which should have been P13 and P14. The error has been corrected in the HTML, PDF and print versions of the paper.
PubMed: 30429576
DOI: 10.1038/s41588-018-0304-8 -
Congenital Anomalies Sep 2019
Topics: Adult; Alleles; Cytoplasmic Dyneins; DNA Mutational Analysis; Female; Genotype; High-Throughput Nucleotide Sequencing; Humans; Pedigree; Pregnancy; Prenatal Diagnosis; Short Rib-Polydactyly Syndrome; Twins, Monozygotic; Ultrasonography, Prenatal
PubMed: 30375052
DOI: 10.1111/cga.12317 -
Nature Genetics Dec 2018Subcutaneous panniculitis-like T cell lymphoma (SPTCL), a non-Hodgkin lymphoma, can be associated with hemophagocytic lymphohistiocytosis (HLH), a life-threatening...
Subcutaneous panniculitis-like T cell lymphoma (SPTCL), a non-Hodgkin lymphoma, can be associated with hemophagocytic lymphohistiocytosis (HLH), a life-threatening immune activation that adversely affects survival. T cell immunoglobulin mucin 3 (TIM-3) is a modulator of immune responses expressed on subgroups of T and innate immune cells. We identify in ~60% of SPTCL cases germline, loss-of-function, missense variants altering highly conserved residues of TIM-3, c.245A>G (p.Tyr82Cys) and c.291A>G (p.Ile97Met), each with specific geographic distribution. The variant encoding p.Tyr82Cys TIM-3 occurs on a potential founder chromosome in patients with East Asian and Polynesian ancestry, while p.Ile97Met TIM-3 occurs in patients with European ancestry. Both variants induce protein misfolding and abrogate TIM-3's plasma membrane expression, leading to persistent immune activation and increased production of inflammatory cytokines, including tumor necrosis factor-α and interleukin-1β, promoting HLH and SPTCL. Our findings highlight HLH-SPTCL as a new genetic entity and identify mutations causing TIM-3 alterations as a causative genetic defect in SPTCL. While HLH-SPTCL patients with mutant TIM-3 benefit from immunomodulation, therapeutic repression of the TIM-3 checkpoint may have adverse consequences.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Diagnosis, Differential; Female; Genetic Predisposition to Disease; Germ-Line Mutation; Hepatitis A Virus Cellular Receptor 2; Humans; Infant; Lymphohistiocytosis, Hemophagocytic; Lymphoma, T-Cell; Male; Middle Aged; Panniculitis; Pedigree; Exome Sequencing; Young Adult
PubMed: 30374066
DOI: 10.1038/s41588-018-0251-4 -
Investigative Ophthalmology & Visual... Sep 2018Mutations in the intraflagellar transport protein 52 homolog (IFT52) gene are reported to interrupt ciliary function and cause short-rib thoracic dysplasia (SRTD), a...
PURPOSE
Mutations in the intraflagellar transport protein 52 homolog (IFT52) gene are reported to interrupt ciliary function and cause short-rib thoracic dysplasia (SRTD), a specific form of skeletal ciliopathy. However, the roles of these mutations in retinal ciliopathy are inexplicit. We herein aim to study the impact of IFT52 mutations in retinopathies.
METHODS
A patient with syndromic ciliopathy, presenting mild SRTD (skeletal ciliopathy) and Liber congenital amaurosis (LCA; retinal ciliopathy), and nine unaffected family members were recruited. Comprehensive systemic evaluations, including ophthalmic tests, were received by the patient. Whole genome sequencing (WGS) was applied for genetic annotation. An in vitro cell system was employed to study the pathogenicity of the variant.
RESULTS
WGS identified a homozygous missense variation in IFT52, c.556A>G (p.T186A), carried by the patient but absent in both unaffected siblings. In silico analysis supported the pathogenic nature of this highly conserved variant. Structural analysis suggested that this substitution could generate a novel hydrogen bond between the mutated residue 186 and proline at residue 192, thus potentially interrupting the tertiary structure and the stability of the IFT52 protein. In vitro cellular study indicated that this mutation might disturb the stability of encoded IFT52 protein and dramatically disrupt cilia elongation in hTERT-RPE1 cells in a loss-of-function manner.
CONCLUSIONS
This report expands ocular phenotypes of IFT52 mutation-caused ciliopathy to include retinal ciliopathy and demonstrates its deleterious nature in interrupting primary ciliary function. Our study hence highlights the need for screening for IFT52 mutations in LCA patients and ophthalmic reviews of patients carrying IFT52 mutations.
Topics: Animals; Carrier Proteins; Child, Preschool; Ciliopathies; Computational Biology; Female; Fluorescent Antibody Technique, Indirect; Humans; Immunoblotting; Intracellular Signaling Peptides and Proteins; Leber Congenital Amaurosis; Mice; Mice, Inbred C57BL; Mutation, Missense; Pedigree; Plasmids; Real-Time Polymerase Chain Reaction; Retinal Degeneration; Retinal Pigment Epithelium; Short Rib-Polydactyly Syndrome; Tomography, Optical Coherence; Transfection; Whole Genome Sequencing
PubMed: 30242358
DOI: 10.1167/iovs.17-23351