SHD, or Sickle Cell Disease, is a genetic blood disorder characterized by the production of abnormal hemoglobin, known as hemoglobin S. This leads to the distortion of red blood cells into a sickle or crescent shape, which can cause blockages in blood vessels, leading to pain and various complications. Individuals with SHD may experience symptoms such as anemia, fatigue, and episodes of severe pain known as sickle cell crises. The disease is inherited in an autosomal recessive pattern, meaning that a person must receive two copies of the sickle cell gene, one from each parent, to develop the condition.