There are obvious regional differences in the number of thalassemia gene carriers, because thalassemia, first found in the Mediterranean coastal countries, is mainly seen in the southern provinces of China, such as Guangxi, Guangdong and Hainan. In these areas, there are relatively more thalassemia gene carriers and patients with thalassemia minor and neutrophilic thalassemia can also be seen. Generally, patients with severe thalassemia often have difficulty reaching the adult level and die young, but in the northern and western regions of China, thalassemia is rarely seen. At the same time, the number of thalassemia gene carriers is small, and it is even more rare to see medium-sized thalassemia patients, because thalassemia gene carriers, if married with normal people, will not produce moderate thalassemia among their offspring, but only normal people or thalassemia gene carriers. However, in the southern region, where the number of thalassemia gene carriers is high, it is easy to produce mild thalassemia and moderate thalassemia patients.