When a mutated gene makes a protein that doesn't function properly, it will result in genetic diseases and will express disease symptoms in the individual. An example is sickle cell anemia. Hemoglobin is a vital protein used by red blood cells to transport oxygen throughout the body. When a mutated gene makes hemoglobin that is altered and does not function properly, it can cause anemia (a condition in which an individual has low healthy red blood cells).
