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.
Overall design: 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.
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