Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Expression variation between VHLR200w homozygous verse wildtype control

ABSTRACT: Hypoxia may cause pulmonary and brain edema, pulmonary hypertension, aberrant metabolism and early mortality. To better understand pathological processes associated with hypoxia, we examined gene expression in Chuvash polycythemia (CP) blood mononuclear cells. CP is a congenital disorder of up-regulated hypoxic response at normoxia wherein VHLR200W homozygosity leads to elevated hypoxia inducible factor (HIF)-1 and HIF-2 levels, thromboses, pulmonary hypertension, lower systemic blood pressure (SBP) and increased mortality. VHLR200W homozygotes are often treated by phlebotomy resulting in iron deficiency, allowing us to evaluate an interaction of augmented hypoxia sensing with iron deficiency. Expression was profiled for 8 VHLR200W homozygotes (CP21, CP23, CP26_2, CP37, CP40, CP43, CP45, CP46) and 17 VHL wildtype individuals (CP48, CP49, CP50, CP51, CP52, CP53, CP55, CP57, CP58, CP59, CP61, CP62, CP63, CP65, CP66, CP67_2, CP68), matched for normal iron status as reflected in serum ferritin concentration. Additional studies including 16 VHLR200W homozygotes with low ferritin (CP22, CP24, CP25, CP28, CP29, CP30, CP31, CP32, CP34, CP35, CP36, CP39, CP41, CP42, CP44, CP47) indicated that iron deficiency generally affects the induction effect of VHLR200W. Two wildtype individuals (CP54, CP56) had no serum ferritin concentration record and two wildtype individuals (CP60, CP64) were defined as iron deficiency subject, which were not included in further expression analysis.

ORGANISM(S): Homo sapiens

SUBMITTER: Xu Zhang

PROVIDER: E-GEOD-40227 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Iron deficiency modifies gene expression variation induced by augmented hypoxia sensing.

Zhang Xu X Zhang Wei W Ma Shwu-Fan SF Miasniakova Galina G Sergueeva Adelina A Ammosova Tatiana T Xu Min M Nekhai Sergei S Nourai Mehdi M Wade Michael S MS Prchal Josef T JT Garcia Joe G N JGN Machado Roberto F RF Gordeuk Victor R VR

Blood cells, molecules & diseases 20130828 1

In congenital Chuvash polycythemia (CP), VHL(R200W) homozygosity leads to elevated hypoxia inducible factor (HIF) levels at normoxia. CP is often treated by phlebotomy resulting in iron deficiency, permitting us to examine the separate and synergistic effects of iron deficiency and HIF signaling on gene expression. We compared peripheral blood mononuclear cell gene expression profiles of eight VHL(R200W) homozygotes with 17 wildtype individuals with normal iron status and found 812 up-regulated ...[more]

PMID: 23993337

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Project description:While blood transcriptional profiling has improved diagnosis and understanding of disease pathogenesis of adult tuberculosis (TB), no studies applying gene expression profiling of children with TB have been described so far. In this study, we have compared whole blood gene expression in childhood TB patients, as well as in healthy latently infected (LTBI) and uninfected (HC) children in a cohort of Warao Amerindians in the Delta Amacuro in Venezuela. We identified a 116-gene signature set by means of random forest analysis that showed an average prediction error of 11% for TB vs. LTBI and for TB vs. LTBI vs. HC in our dataset. Furthermore, a minimal set of only 9 genes showed a significant predictive value for all previously published adult studies using whole blood gene expression, with average prediction errors between 17% and 23%. 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Dataset Information

Expression variation between VHLR200w homozygous verse wildtype control

Publications

Iron deficiency modifies gene expression variation induced by augmented hypoxia sensing.

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