How many alpha Hb chain genes are present in normal human physiology?

In normal human physiology, there are four alpha globin (Hb) chain genes located on chromosome 16. These genes are responsible for the production of the alpha chains of hemoglobin, which combine with beta chains to form the functional hemoglobin molecule, essential for oxygen transport in the blood.

The presence of four alpha genes allows for a robust production of alpha globin chains, ensuring that each hemoglobin molecule is correctly formed during erythropoiesis (the production of red blood cells). If there is a mutation or deletion in one or more of these alpha genes, it can lead to various forms of alpha thalassemia, where the synthesis of hemoglobin is compromised, resulting in anemia and associated symptoms.

Understanding the normal number of alpha globin genes is crucial for recognizing disorders related to hemoglobin synthesis and for guiding the diagnosis and treatment of these conditions.