According to Iwasa (undated), the conformation of an oxygenated hemoglobin is referred to as relaxed (R) state, while the deoxygenated one is in taut (T) conformation state. In the taut conformation, the iron molecule is non-planar in relation to the remaining part of the heme group. This non-planar relationship is caused the interaction between the iron molecule and the histidine side chain. However, when the iron binds to oxygen, it changes it position relative to the remaining heme group. This change the position of the iron molecule results in the molecule being planar with the remaining part of the heme group. Also, while changing its position, the iron molecule pulls the histidine. The histidine position relative to the remainder of the hemoglobin subunit therefore changes. These changes in the position of iron molecule and histidine causes the conformation of the protein to change. Hemoglobin therefore exist in duo state both chemically and structurally (Iwasa, …show more content…
The gene can be inherited from any parent with a heterozygous genotype. Any person who has heterozygous genotype is a carrier of sickle cell anemia, a condition normally referred to as sickle cell trait. Individuals with sickle cell trait do not suffer from sickle cell anemia. Any two parents with heterozygous genotype has a 25 per cent chance of producing a child with sickle cell anemia. This will only occur if the child has inherited a mutated gene from both parents. On the other hand, such parents have a 50 % chance to produce a child who has heterozygous genotype. This is the case when a child has inherited the mutated gene from only one parent. There is also case where a child from such parents would not inherit a mutated gene from either parent. The chances of producing such a child is 25%. Since the mutated gene that causes sickle cell anemia is not expressed in individuals with heterozygous genotype, then the mutated gene is a recessive gene (Wolfe,