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131.
132.
Anderson BH Kasher PR Mayer J Szynkiewicz M Jenkinson EM Bhaskar SS Urquhart JE Daly SB Dickerson JE O'Sullivan J Leibundgut EO Muter J Abdel-Salem GM Babul-Hirji R Baxter P Berger A Bonafé L Brunstom-Hernandez JE Buckard JA Chitayat D Chong WK Cordelli DM Ferreira P Fluss J Forrest EH Franzoni E Garone C Hammans SR Houge G Hughes I Jacquemont S Jeannet PY Jefferson RJ Kumar R Kutschke G Lundberg S Lourenço CM Mehta R Naidu S Nischal KK Nunes L Ounap K Philippart M Prabhakar P Risen SR 《Nature genetics》2012,44(3):338-342
Coats plus is a highly pleiotropic disorder particularly affecting the eye, brain, bone and gastrointestinal tract. Here, we show that Coats plus results from mutations in CTC1, encoding conserved telomere maintenance component 1, a member of the mammalian homolog of the yeast heterotrimeric CST telomeric capping complex. Consistent with the observation of shortened telomeres in an Arabidopsis CTC1 mutant and the phenotypic overlap of Coats plus with the telomeric maintenance disorders comprising dyskeratosis congenita, we observed shortened telomeres in three individuals with Coats plus and an increase in spontaneous γH2AX-positive cells in cell lines derived from two affected individuals. CTC1 is also a subunit of the α-accessory factor (AAF) complex, stimulating the activity of DNA polymerase-α primase, the only enzyme known to initiate DNA replication in eukaryotic cells. Thus, CTC1 may have a function in DNA metabolism that is necessary for but not specific to telomeric integrity. 相似文献
133.
Extremely low-coverage sequencing and imputation increases power for genome-wide association studies 总被引:1,自引:0,他引:1
Pasaniuc B Rohland N McLaren PJ Garimella K Zaitlen N Li H Gupta N Neale BM Daly MJ Sklar P Sullivan PF Bergen S Moran JL Hultman CM Lichtenstein P Magnusson P Purcell SM Haas DW Liang L Sunyaev S Patterson N de Bakker PI Reich D Price AL 《Nature genetics》2012,44(6):631-635
Genome-wide association studies (GWAS) have proven to be a powerful method to identify common genetic variants contributing to susceptibility to common diseases. Here, we show that extremely low-coverage sequencing (0.1-0.5×) captures almost as much of the common (>5%) and low-frequency (1-5%) variation across the genome as SNP arrays. As an empirical demonstration, we show that genome-wide SNP genotypes can be inferred at a mean r(2) of 0.71 using off-target data (0.24× average coverage) in a whole-exome study of 909 samples. Using both simulated and real exome-sequencing data sets, we show that association statistics obtained using extremely low-coverage sequencing data attain similar P values at known associated variants as data from genotyping arrays, without an excess of false positives. Within the context of reductions in sample preparation and sequencing costs, funds invested in extremely low-coverage sequencing can yield several times the effective sample size of GWAS based on SNP array data and a commensurate increase in statistical power. 相似文献
134.
Harakalova M van Harssel JJ Terhal PA van Lieshout S Duran K Renkens I Amor DJ Wilson LC Kirk EP Turner CL Shears D Garcia-Minaur S Lees MM Ross A Venselaar H Vriend G Takanari H Rook MB van der Heyden MA Asselbergs FW Breur HM Swinkels ME Scurr IJ Smithson SF Knoers NV van der Smagt JJ Nijman IJ Kloosterman WP van Haelst MM van Haaften G Cuppen E 《Nature genetics》2012,44(7):793-796
Cantú syndrome is characterized by congenital hypertrichosis, distinctive facial features, osteochondrodysplasia and cardiac defects. By using family-based exome sequencing, we identified a de novo mutation in ABCC9. Subsequently, we discovered novel dominant missense mutations in ABCC9 in 14 of the 16 individuals with Cantú syndrome examined. The ABCC9 protein is part of an ATP-dependent potassium (K(ATP)) channel that couples the metabolic state of a cell with its electrical activity. All mutations altered amino acids in or close to the transmembrane domains of ABCC9. Using electrophysiological measurements, we show that mutations in ABCC9 reduce the ATP-mediated potassium channel inhibition, resulting in channel opening. Moreover, similarities between the phenotype of individuals with Cantú syndrome and side effects from the K(ATP) channel agonist minoxidil indicate that the mutations in ABCC9 result in channel opening. Given the availability of ABCC9 antagonists, our findings may have direct implications for the treatment of individuals with Cantú syndrome. 相似文献
135.
Wan J Yourshaw M Mamsa H Rudnik-Schöneborn S Menezes MP Hong JE Leong DW Senderek J Salman MS Chitayat D Seeman P von Moers A Graul-Neumann L Kornberg AJ Castro-Gago M Sobrido MJ Sanefuji M Shieh PB Salamon N Kim RC Vinters HV Chen Z Zerres K Ryan MM Nelson SF Jen JC 《Nature genetics》2012,44(6):704-708
RNA exosomes are multi-subunit complexes conserved throughout evolution and are emerging as the major cellular machinery for processing, surveillance and turnover of a diverse spectrum of coding and noncoding RNA substrates essential for viability. By exome sequencing, we discovered recessive mutations in EXOSC3 (encoding exosome component 3) in four siblings with infantile spinal motor neuron disease, cerebellar atrophy, progressive microcephaly and profound global developmental delay, consistent with pontocerebellar hypoplasia type 1 (PCH1; MIM 607596). We identified mutations in EXOSC3 in an additional 8 of 12 families with PCH1. Morpholino knockdown of exosc3 in zebrafish embryos caused embryonic maldevelopment, resulting in small brain size and poor motility, reminiscent of human clinical features, and these defects were largely rescued by co-injection with wild-type but not mutant exosc3 mRNA. These findings represent the first example of an RNA exosome core component gene that is responsible for a human disease and further implicate dysregulation of RNA processing in cerebellar and spinal motor neuron maldevelopment and degeneration. 相似文献
136.
Roscioli T Kamsteeg EJ Buysse K Maystadt I van Reeuwijk J van den Elzen C van Beusekom E Riemersma M Pfundt R Vissers LE Schraders M Altunoglu U Buckley MF Brunner HG Grisart B Zhou H Veltman JA Gilissen C Mancini GM Delrée P Willemsen MA Ramadža DP Chitayat D Bennett C Sheridan E Peeters EA Tan-Sindhunata GM de Die-Smulders CE Devriendt K Kayserili H El-Hashash OA Stemple DL Lefeber DJ Lin YY van Bokhoven H 《Nature genetics》2012,44(5):581-585
Walker-Warburg syndrome (WWS) is an autosomal recessive multisystem disorder characterized by complex eye and brain abnormalities with congenital muscular dystrophy (CMD) and aberrant a-dystroglycan glycosylation. Here we report mutations in the ISPD gene (encoding isoprenoid synthase domain containing) as the second most common cause of WWS. Bacterial IspD is a nucleotidyl transferase belonging to a large glycosyltransferase family, but the role of the orthologous protein in chordates is obscure to date, as this phylum does not have the corresponding non-mevalonate isoprenoid biosynthesis pathway. Knockdown of ispd in zebrafish recapitulates the human WWS phenotype with hydrocephalus, reduced eye size, muscle degeneration and hypoglycosylated a-dystroglycan. These results implicate ISPD in a-dystroglycan glycosylation in maintaining sarcolemma integrity in vertebrates. 相似文献
137.
138.
S Peña-Llopis S Vega-Rubín-de-Celis A Liao N Leng A Pavía-Jiménez S Wang T Yamasaki L Zhrebker S Sivanand P Spence L Kinch T Hambuch S Jain Y Lotan V Margulis AI Sagalowsky PB Summerour W Kabbani SW Wong N Grishin M Laurent XJ Xie CD Haudenschild MT Ross DR Bentley P Kapur J Brugarolas 《Nature genetics》2012,44(9):1072
139.
RK Koenekoop H Wang J Majewski X Wang I Lopez H Ren Y Chen Y Li GA Fishman M Genead J Schwartzentruber N Solanki EI Traboulsi J Cheng CV Logan M McKibbin BE Hayward DA Parry CA Johnson M Nageeb;Finding of Rare Disease Genes 《Nature genetics》2012,44(9):1035-1039
Leber congenital amaurosis (LCA) is a blinding retinal disease that presents within the first year after birth. Using exome sequencing, we identified mutations in the nicotinamide adenine dinucleotide (NAD) synthase gene NMNAT1 encoding nicotinamide mononucleotide adenylyltransferase 1 in eight families with LCA, including the family in which LCA was originally linked to the LCA9 locus. Notably, all individuals with NMNAT1 mutations also have macular colobomas, which are severe degenerative entities of the central retina (fovea) devoid of tissue and photoreceptors. Functional assays of the proteins encoded by the mutant alleles identified in our study showed that the mutations reduce the enzymatic activity of NMNAT1 in NAD biosynthesis and affect protein folding. Of note, recent characterization of the slow Wallerian degeneration (Wld(s)) mouse model, in which prolonged axonal survival after injury is observed, identified NMNAT1 as a neuroprotective protein when ectopically expressed. Our findings identify a new disease mechanism underlying LCA and provide the first link between endogenous NMNAT1 dysfunction and a human nervous system disorder. 相似文献
140.
The maintenance of mucosal barrier equilibrium in the intestine requires a delicate and dynamic balance between enterocyte
loss by apoptosis and the generation of new cells by proliferation from stem cell precursors at the base of the intestinal
crypts. When the balance shifts towards either excessive or insufficient apoptosis, a broad range of gastrointestinal diseases
can manifest. Recent work from a variety of laboratories has provided evidence in support of a role for receptors of the innate
immune system, including Toll-like receptors 2, 4, and 9 as well as the intracellular pathogen recognition receptor NOD2/CARD15,
in the initiation of enterocyte apoptosis. The subsequent induction of enterocyte apoptosis in response to the activation
of these innate immune receptors plays a key role in the development of various intestinal diseases, including necrotizing
enterocolitis, Crohn’s disease, ulcerative colitis, and intestinal cancer. This review will detail the regulatory pathways
that govern enterocyte apoptosis, and will explore the role of the innate immune system in the induction of enterocyte apoptosis
in gastrointestinal disease. 相似文献