Recent research shows that MPO is an emerging biomarker to assess cardiovascular diseases (CVD) and endothelial dysfunction in vivo (Eiserich et al., 2002; Brennan & Hazen, 2003) as human subjects with significantly lower risks of CVD were found to have less MPO activity and vice-versa (Zhang et al., 2001). This evidence concerns the gene MPO and endothelial dysfunction.