%0 Journal Article %T Expression profiling identifies genes involved in emphysema severity %A Santiyagu Francis %A Jill E Larsen %A Sandra J Pavey %A Rayleen V Bowman %A Nicholas K Hayward %A Kwun M Fong %A Ian A Yang %J Respiratory Research %D 2009 %I BioMed Central %R 10.1186/1465-9921-10-81 %X Gene expression profiling was performed on total RNA extracted from non-tumor lung tissue from 30 smokers with emphysema. Class comparison analysis based on gas transfer measurement was performed to identify differentially expressed genes. Genes were then selected for technical validation by quantitative reverse transcriptase-PCR (qRT-PCR) if also represented on microarray platforms used in previously published emphysema studies. Genes technically validated advanced to tests of biological replication by qRT-PCR using an independent test set of 62 lung samples.Class comparison identified 98 differentially expressed genes (p < 0.01). Fifty-one of those genes had been previously evaluated in differentiation between normal and severe emphysema lung. qRT-PCR confirmed the direction of change in expression in 29 of the 51 genes and 11 of those validated, remaining significant at p < 0.05. Biological replication in an independent cohort confirmed the altered expression of eight genes, with seven genes differentially expressed by greater than 1.3 fold, identifying these as candidate determinants of emphysema severity.Gene expression profiling of lung from emphysema patients identified seven candidate genes associated with emphysema severity including COL6A3, SERPINF1, ZNHIT6, NEDD4, CDKN2A, NRN1 and GSTM3.Chronic obstructive pulmonary disease (COPD) is a major health burden worldwide [1]. Smoking is the primary cause of COPD, with up to 50% of smokers developing the disease [2]. It is frequently under-diagnosed and under-treated [3] since its early stages are often asymptomatic. COPD patients are classified into mild, moderate and severe based on the degree of airflow limitation, which is a result of damage in the large airways (bronchitis), small airways (bronchiolitis) and or alveoli (emphysema). Emphysema affects 40% of heavy smokers [4] and causes loss of elastic recoil, leading to abnormal gas exchange and breathlessness. Despite smoking cessation, some individuals con %U http://respiratory-research.com/content/10/1/81