Copy-number variation in BMPR2 is not associated with the pathogenesis of pulmonary arterial hypertension

<p>Abstract</p> <p>Background</p> <p>Copy-number variations (CNVs) are structural variations in the genome involving 1 kb to 3 mb of DNA. CNV has been reported within intron 1 of the <it>BMPR2 </it>gene. We propose that CNV could affect phenotype in familial and/or sporadic pulmonary arterial hypertension (PAH) by altering gene expression.</p> <p>Methods</p> <p>97 human DNA samples were obtained which included 24 patients with familial PAH, 18 obligate carriers (<it>BMPR2 </it>mutation positive), 20 sporadic PAH patients, and 35 controls. Two sets of primers were designed within the CNV, and two sets of control primers were designed outside the CNV. Quantitative PCR was performed to quantify genomic copies of CNV and control sequences.</p> <p>Results</p> <p>A CNV in <it>BMPR2 </it>was present in one African American negative control subject.</p> <p>Conclusion</p> <p>We conclude that the CNV in intron 1 in <it>BMPR2 </it>is unlikely to play a role in the pathogenesis of either familial or sporadic PAH.</p> <p>Trial Registration</p> <p>NIH NCT00091546.</p

Gene expression in BMPR2 mutation carriers with and without evidence of Pulmonary Arterial Hypertension suggests pathways relevant to disease penetrance

<p>Abstract</p> <p>Background</p> <p>While BMPR2 mutation strongly predisposes to pulmonary arterial hypertension (PAH), only 20% of mutation carriers develop clinical disease. This finding suggests that modifier genes contribute to FPAH clinical expression. Since modifiers are likely to be common alleles, this problem is not tractable by traditional genetic approaches. Furthermore, examination of gene expression is complicated by confounding effects attributable to drugs and the disease process itself.</p> <p>Methods</p> <p>To resolve these problems, B-cells were isolated, EBV-immortalized, and cultured from familial PAH patients with BMPR2 mutations, mutation positive but disease-free family members, and family members without mutation. This allows examination of differences in gene expression without drug or disease-related effects. These differences were assayed by Affymetrix array, with follow-up by quantitative RT-PCR and additional statistical analyses.</p> <p>Results</p> <p>By gene array, we found consistent alterations in multiple pathways with known relationship to PAH, including actin organization, immune function, calcium balance, growth, and apoptosis. Selected genes were verified by quantitative RT-PCR using a larger sample set. One of these, CYP1B1, had tenfold lower expression than control groups in female but not male PAH patients. Analysis of overrepresented gene ontology groups suggests that risk of disease correlates with alterations in pathways more strongly than with any specific gene within those pathways.</p> <p>Conclusion</p> <p>Disease status in BMPR2 mutation carriers was correlated with alterations in proliferation, GTP signaling, and stress response pathway expression. The estrogen metabolizing gene CYP1B1 is a strong candidate as a modifier gene in female PAH patients.</p

Ancestral Mutation in Telomerase Causes Defects in Repeat Addition Processivity and Manifests As Familial Pulmonary Fibrosis

The telomerase reverse transcriptase synthesizes new telomeres onto chromosome ends by copying from a short template within its integral RNA component. During telomere synthesis, telomerase adds multiple short DNA repeats successively, a property known as repeat addition processivity. However, the consequences of defects in processivity on telomere length maintenance are not fully known. Germline mutations in telomerase cause haploinsufficiency in syndromes of telomere shortening, which most commonly manifest in the age-related disease idiopathic pulmonary fibrosis. We identified two pulmonary fibrosis families that share two non-synonymous substitutions in the catalytic domain of the telomerase reverse transcriptase gene hTERT: V791I and V867M. The two variants fell on the same hTERT allele and were associated with telomere shortening. Genealogy suggested that the pedigrees shared a single ancestor from the nineteenth century, and genetic studies confirmed the two families had a common founder. Functional studies indicated that, although the double mutant did not dramatically affect first repeat addition, hTERT V791I-V867M showed severe defects in telomere repeat addition processivity in vitro. Our data identify an ancestral mutation in telomerase with a novel loss-of-function mechanism. They indicate that telomere repeat addition processivity is a critical determinant of telomere length and telomere-mediated disease

Alzheimer's Disease Amyloid-β Links Lens and Brain Pathology in Down Syndrome

Down syndrome (DS, trisomy 21) is the most common chromosomal disorder and the leading genetic cause of intellectual disability in humans. In DS, triplication of chromosome 21 invariably includes the APP gene (21q21) encoding the Alzheimer's disease (AD) amyloid precursor protein (APP). Triplication of the APP gene accelerates APP expression leading to cerebral accumulation of APP-derived amyloid-β peptides (Aβ), early-onset AD neuropathology, and age-dependent cognitive sequelae. The DS phenotype complex also includes distinctive early-onset cerulean cataracts of unknown etiology. Previously, we reported increased Aβ accumulation, co-localizing amyloid pathology, and disease-linked supranuclear cataracts in the ocular lenses of subjects with AD. Here, we investigate the hypothesis that related AD-linked Aβ pathology underlies the distinctive lens phenotype associated with DS. Ophthalmological examinations of DS subjects were correlated with phenotypic, histochemical, and biochemical analyses of lenses obtained from DS, AD, and normal control subjects. Evaluation of DS lenses revealed a characteristic pattern of supranuclear opacification accompanied by accelerated supranuclear Aβ accumulation, co-localizing amyloid pathology, and fiber cell cytoplasmic Aβ aggregates (∼5 to 50 nm) identical to the lens pathology identified in AD. Peptide sequencing, immunoblot analysis, and ELISA confirmed the identity and increased accumulation of Aβ in DS lenses. Incubation of synthetic Aβ with human lens protein promoted protein aggregation, amyloid formation, and light scattering that recapitulated the molecular pathology and clinical features observed in DS lenses. These results establish the genetic etiology of the distinctive lens phenotype in DS and identify the molecular origin and pathogenic mechanism by which lens pathology is expressed in this common chromosomal disorder. Moreover, these findings confirm increased Aβ accumulation as a key pathogenic determinant linking lens and brain pathology in both DS and AD

Redesigning School Nursing Education in New Jersey to Address the Challenges and Opportunities of Population Health

School health is a specialty practice of nursing positioned at the intersection of public health and population health. This article discusses the redesign of a program’s curriculum with the hope of advancing and elevating the practice of school nursing. The redesign is based on NASN’s Framework for 21st Century School Nursing Practice and is the result of a New Jersey Nursing Initiative grant awarded to a trio of adjunct faculty from Rutgers University Camden in July 2016. </jats:p

Phenotypic Determinants of Adenovirus E1A Gene Autoregulation: Variable Region between Conserved Coding Domains 2 and 3

AbstractDifferent serotypes and evolutionary variants of human adenoviruses exhibit distinctive patterns of positive and negative autoregulation of the viral E1A gene. An autoregulatory E1A promoter mutation of the adenovirus type 3 (Ad3) E1A gene renders Ad3hr15 incapable of growth in normally permissive cells. The promoter mutation is complementedin transby E1A products of the heterologous helper adenovirus type 5 (Ad5). Second-site revertants of Ad3hr15 restore viability with high levels of E1A gene expression. The revertant E1A genotypes retain the mutant E1A promoter and have small in-frame deletions in the nonconserved region between the repression- and activation-associated conserved domains CR2 and CR3. Plasmid expression vectors were constructed as 12S and 13S cDNA forms of revertant E1A genes. These were used in cotransfection experiments with a reporter gene plasmid under transcriptional control of the mutant Ad3hr15 E1A promoter. The repression of the Ad3hr15 E1A promoter by helper Ad5 or revertant 12S E1A cDNA was consistently greater than that effected by wild-type Ad3 12S E1A cDNA expression. Significantly greater levels of positive transactivation were observed in cotransfections with 13S cDNAs of Ad5 or with the 13S E1A cDNA of Ad3hr15 revertants, compared to the transactivation observed with the mutant-encoded wild-type Ad3 13S E1A cDNA. The Ad5 helper anddl-revertant phenotype of Ad3hr15 appear to be related to transactivation activities of coexpressed E1A genes. The nonconserved region which separates the conserved coding regions CR2 and CR3 of the type 3 E1A gene acts to attenuate E1A-mediated repression and transactivation of transcription