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 D-Punjab Hemoglobin D-Punjab Hemoglobin D-Punjab is one of the sub-variants of Hemoglobin D, a variant of hemoglobin found in human blood. It is so named because of its higher prevalence in the Punjab region of India and Pakistan. It is also the most frequent abnormal hemoglobin variant in Xinjiang Uyghur Autonomous Region of China. Studies indicate that Hemoglobin D-Punjab accounts for over 55% of the total hemoglobin variants there. Hemoglobin D-Punjab was first discovered in the early 1950s in a mixed British and American family of Indian origin from the Los Angeles area; hence it is also sometimes called “D Los