Hemoglobin by molecules such as carbon monoxide (for example, from tobacco smoking, exhaust gas, and incomplete combustion in furnaces). CO competes with oxygen at the heme binding site. Hemoglobin's binding affinity for CO is 250 times greater than its affinity for oxygen, meaning that small amounts of CO dramatically reduce hemoglobin's ability to transport oxygen. Since carbon monoxide is a colorless, odorless and tasteless gas, and poses a potentially fatal threat, carbon monoxide detectors have become commercially available to warn of dangerous levels in residences. When hemoglobin combines with CO, it forms a very bright red compound called carboxyhemoglobin, which may
Hemoglobin E health problems. They may have a low mean corpuscular volume (MCV) and very abnormal red blood cells (target cells), but clinical relevance is mainly due to the potential for transmitting E or β-thalassemia. Compound heterozygotes with hemoglobin sickle E disease result when the gene of hemoglobin E is inherited from one parent and the gene for hemoglobin S from the other. As the amount of fetal hemoglobin decreases and hemoglobin S increases, a mild hemolytic anemia appears in the early stage of development. People who have hemoglobin E/β-thalassemia have inherited one gene for hemoglobin E from one parent and one