Why are Genes involved in the production of abnormal red blood cells have an abnormal sequence of?

Genes involved in the production of abnormal red blood cells often have an abnormal sequence due to mutations that alter the structure and function of hemoglobin or other proteins essential for red blood cell formation. These mutations can lead to conditions such as sickle cell disease or thalassemia, where the red blood cells become misshapen, fragile, or unable to effectively carry oxygen. The abnormal sequences can be inherited or arise spontaneously, affecting the overall health and functionality of the blood cells.