[Analysis and Prevention of Gene Mutation Types of Severe Thala- ssemia in Hakka People in Gannan of Jiangxi Province].

OBJECTIVE

To investigate the types and proportion of gene mutations of thalassemia in Hakka people in Gannan Area of Jiangxi, and to provide some references for prevention and treatment of thalassemia major, genetic counseling and epidemiological studies.

METHODS

81 cases Hakka patients with severe thalassemia admitted treated in First Affiliated Hospital of Gannan Medical College from January 2009 to June 2019 were enrolled. The deletion type of α-thalassemia was detected by Gap-PCR. The point mutations of α-thalassemia and β-thalassemia were detected by PCR-RDB. The thalassemia gene was detected and analyzed in the patients with anemia, and the frequency of gene mutation was calculated.

RESULTS

Among 81 Hakka patients with thalassemia major, 4 β-thalassemia (homozygote) genotypes were detected out, including: CD41-42（TTCT）(19 cases), β-IVS-II-654 (C→T) (9 cases), -28M (A→G) (1 case), CD17 (A→T) (1 case); 12 β-thalassemithalassemia (heterozygote) genotypes were detected out, including: CD41-42(-TTCT)/β-IVS-II-654(C→T) (15 cases, 29.41%), β-IVS-II-654(C→T)/β-28M(A→G) (13 cases，25.49%) ； CD41-42(-TTCT)/β-28M(A→G) (9 cases，17.65%); β-IVS-II-654(C→T) /CD27/28(+C) (3 cases， 5.88%) ； CD41-42(-TTCT)/CD27/28(+C)(3 case，5.88%)；β-28M(A→G)/CD17(A→T) (2 cases，3.92%)；CD41-42(-TTCT)/CD17(A→T), CD41-42(-TTCT)/Βe, β-IVS-II-654(C→T)/β-29、βCD17（A→T）/CD71-72(+a), βCD71-72/β-28M(A→G), β-28M(A→G) /β-IVS-II-654(C→T)(1 cases，1.96%). There were 3 cases of β homozygous thalassemia with α-thalassemia gene and 5 cases of β heterozygotes thalassemia with α-thalassemia gene.

CONCLUSION

The incidence rate of thalassemia in Hakka people in Gannan Area of Jiangxi is relatively high. The distribution of gene mutation types is as follows: the genotype of CD41-42 (-TTCT) is the main genotype of β-thalassemia (homozygous); the major genotypes of β- thalassemia (heterozygotes) are CD41-42 (-TTCT)/β-IVS-II-654 (C→T) and β-IVS-II-654 (C→T) /β-28M (A→G); CD41-42 (-TTCT) gene is dominant in β-complex α-thalassemia.