Thalassemia, formerly known as Mediterranean anemia or oceanic anemia, is a hereditary hemolytic anemia caused by mutations or deletions in globin genes, leading to insufficient synthesis of globin peptide chains. Those who lack beta chains are referred to as having beta-thalassemia, and those who lack alpha chains are known as having alpha-thalassemia. Clinically, it is classified into mild, intermediate, and severe forms based on the severity of anemia. The disease is widespread in many regions of the world, including the Mediterranean, the Middle East, Africa, Southeast Asia, and southern China. In China, it is more commonly found in Guangxi, Guangdong, Sichuan, Hong Kong, northern Taiwan, Yunnan, Guizhou, Hainan, Fujian, Hunan, and Hubei, and less commonly in the north. Thalassemia is fundamentally defined not as leukemia, but as a genetic disease.