[Analysis of Thalassemia Gene Mutation Types and Ethnic Distribution Characteristics in Hechi Area, Guangxi]

To investigate the genotype, mutation type, and ethnic distribution characteristics of thalassemia in the population of Hechi area, Guangxi, and to provide a reference basis for prevention and control of thalassemia and eugenic counseling in the region.

Gap-polymerase chain reaction (gap-PCR) and reverse dot blot (RDB) were used for genetic testing on suspected thalassemia persons, and the results were analyzed.

Among 29 136 samples, a total of 17 016 (58.40%) positive samples for thalassemia genes were detected, with a higher detection rate in males than in females (χ²=49.917，P < 0.001). The detection rates of thalassemia genes were significant different among Zhuang, Han, Yao, Mulao, and Maonan ethnic groups (χ²=546.121, P < 0.001). The α-thalassemia genotypes were mainly -- /αα (16.67%), -α/αα (8.90%), α α/αα (6.00%). Additionally, four rare genotypes were detected, including -- /αα (47 cases), HKαα/αα (2 cases), -- /-α (2 cases), and -- /αα (1 case). The β-thalassemia genotypes were mainly β /β (7.49%), β/β (6.70%), β/β (0.44%). 108 cases of moderate and severe β-thalassemia were detected, of which 81 cases had a history of blood transfusion, the transfusion frequency of 60 cases was more than 10 times/year, and 10 cases received bone marrow transplantation.

Thalassemia in Hechi area is predominantly deletion type -- /αα, the detection rate of thalassemia in ethnic minorities is higher than that in Han population. In this area, moderate and severe β-thalassemia have certain incidence, these patients mostly need regular blood transfusion and iron removal treatment, and very few patients have received bone marrow transplantation. This study provides a certain reference basis for prevention and control of thalassemia and eugenic counseling in the region.