8 research outputs found
Sequence Variation in DDAH1 and DDAH2 Genes Is Strongly and Additively Associated with Serum ADMA Concentrations in Individuals with Type 2 Diabetes
Copyright: © 2010 Abhary et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Asymmetric dimethylarginine (ADMA), present in human serum, is an endogenous inhibitor of nitric oxide synthase and contributes to vascular disease. Dimethylarginine dimethylaminohydrolase (DDAH) is an ADMA degrading enzyme that has two isoforms: DDAHI and DDAHII. We sought to determine whether serum ADMA levels in type 2 diabetes are influenced by common polymorphisms in the DDAH1 and DDAH2 genes
Recurrent mutation in the crystallin alpha A gene associated with inherited paediatric cataract
© 2016 Javadiyan et al. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License
(http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium,
provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license,
and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/
publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: Cataract is a major cause of childhood blindness worldwide. The purpose of this study was to determine
the genetic cause of paediatric cataract in a South Australian family with a bilateral lamellar paediatric cataract
displaying variable phenotypes.
Case presentation: Fifty-one genes implicated in congenital cataract in human or mouse were sequenced in an
affected individual from an Australian (Caucasian) family using a custom Ampliseq library on the Ion Torrent Personal
Genome Machine. Reads were mapped against the human genome (hg19) and variants called with the Torrent Suite
software. Variants were annotated to dbSNP 137 using Ion Reporter (IR 1.6.2) and were prioritised for validation if they
were novel or rare and were predicted to be protein changing. We identified a previously reported oligomerization
disrupting mutation, c.62G > A (p.R21Q), in the Crystallin alpha A (CRYAA) gene segregating in this three generation
family. No other novel or rare coding mutations were detected in the known cataract genes sequenced. Microsatellite
markers were used to compare the haplotypes between the family reported here and a previously published family
with the same segregating mutation. Haplotype analysis indicated a potential common ancestry between the two
South Australian families with this mutation. The work strengthens the genotype-phenotype correlations between
this functional mutation in the crystallin alpha A (CRYAA) gene and paediatric cataract.
Conclusion: The p.R21Q mutation is the most likely cause of paediatric cataract i
Partial duplication of the CRYBB1-CRYBA4 locus is associated with autosomal dominant congenital cataract
This author accepted manuscript is made available following 6 month embargo from date of publication (March 2017) in accordance with the publisher’s copyright policyCongenital cataract is a rare but severe paediatric visual impediment, often caused by variants in one of several crystallin genes that produce the bulk of structural proteins in the lens. Here we describe a pedigree with autosomal dominant isolated congenital cataract and linkage to the crystallin gene cluster on chromosome 22. No rare single nucleotide variants or short indels were identified by exome sequencing, yet copy number variant analysis revealed a duplication spanning both CRYBB1 and CRYBA4. While the CRYBA4 duplication was complete, the CRYBB1 duplication was not, with the duplicated CRYBB1 product predicted to create a gain of function allele. This association suggests a new genetic mechanism for the development of isolated congenital cataract
High throughput genetic screening of 51 paediatric cataract genes identifies causative mutations in inherited paediatric cataract in South Eastern Australia
This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/ licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Paediatric cataract is a leading cause of childhood blindness. This study aimed to determine the genetic cause of paediatric cataract in Australian families by screening known disease associated genes using massively parallel sequencing technology. We sequenced 51 previously reported paediatric cataract genes in 33 affected individuals with a family history (cases with previously known or published mutations were excluded) using the Ion Torrent Personal Genome Machine. Variants were prioritised for validation if they were predicted to alter the protein sequence and were absent or rare with minor allele frequency <1% in public databases. Confirmed mutations were assessed for segregation with the phenotype in all available family members. All identified novel or previously reported cataract causing mutations were screened in 326 unrelated Australian controls. We detected eleven novel mutations in GJA3, GJA8, CRYAA, CRYBB2, CRYGS, CRYGA, GCNT2, CRYGA and MIP, three previously reported cataract causing mutations in GJA8, CRYAA and CRYBB2. The most commonly mutated genes were those coding for gap junctions and crystallin proteins. Including previous reports of paediatric cataract associated mutations in our Australian cohort, known genes account for more than 60 % of familial paediatric cataract in Australia, indicating that still more causative genes remain to be identified
Role of AtAMT1;2 in nitrogen uptake and plant growth.
In Arabidopsis, six ammonium transporters mediate the movement of ammonium in or out of
cells. Uncertainty exists about their individual location and role, either in primary ammonium
uptake or in intercellular translocation of ammonium. Using the endogenous AMT1;2 promoter
to drive an AMT1;2:GFP fusion construct, it was shown that AMT1;2 is primarily localised to
root endodermal and cortical cells, while in shoots natural fluorescence in the leaves prevented
definitive localisation in cells and internal organelles (e.g. chloroplasts). A growth analysis of
amt1;2 and its corresponding wild type parental line revealed improved growth of an amt1;2 TDNA
insertion line in media containing 2 mM KNO3. No difference in growth was observed in
media containing 1 mM NH4NO3. Using 15N to measure net NH4
+ and NO3
- uptake suggested the
growth response in the amt1;2 line was not a result of improved nitrogen uptake. Furthermore,
examination of high affinity ammonium transport in the amt1;2 and WT lines revealed no
detectable difference in ammonium uptake in either N-starved or N-sufficient grown plants
respectively.Thesis (M.Bio (PB)) - University of Adelaide, School of Agriculture, Food and Wine, 200
Novel missense mutation in the bZIP transcription factor, MAF, associated with congenital cataract, developmental delay, seizures and hearing loss (Aymé-Gripp syndrome)
This is an open access article. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated
Angiopoietin receptor TEK mutations underlie primary congenital glaucoma with variable expressivity
Published version made available in accordance publisher policy. Article available freely at PubMed Central (PMC). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4922711/Primary congenital glaucoma (PCG) is a devastating eye disease and an important cause of childhood blindness worldwide. In PCG, defects in the anterior chamber aqueous humor outflow structures of the eye result in elevated intraocular pressure (IOP); however, the genes and molecular mechanisms involved in the etiology of these defects have not been fully characterized. Previously, we observed PCG-like phenotypes in transgenic mice that lack functional angiopoietin-TEK signaling. Herein, we identified rare TEK variants in 10 of 189 unrelated PCG families and demonstrated that each mutation results in haploinsufficiency due to protein loss of function. Multiple cellular mechanisms were responsible for the loss of protein function resulting from individual TEK variants, including an absence of normal protein production, protein aggregate formation, enhanced proteasomal degradation, altered subcellular localization, and reduced responsiveness to ligand stimulation. Further, in mice, hemizygosity for Tek led to the formation of severely hypomorphic Schlemm’s canal and trabecular meshwork, as well as elevated IOP, demonstrating that anterior chamber vascular development is sensitive to Tek gene dosage and the resulting decrease in angiopoietin-TEK signaling. Collectively, these results identify TEK mutations in patients with PCG that likely underlie disease and are transmitted in an autosomal dominant pattern with variable expressivity