On the other hand, in myocardial ischemia/infarction, peripheral vascular disease or the Raynaud’s phenomenon, an increased Hb-O2 affinity might aggravate poor oxygenation due to constrained Hb-O2 unloading in the tissue at risk (e.g., myocardium, peripheral soft tissue). This evidence concerns the gene GSTM1 and myocardial ischemia.