The gene spectrum of thalassemia in Yangjiang of western Guangdong Province

作者：Liang, Hong-Feng; Liang, Wei-Min; Xie, Wen-Guang; Lin, Fen; Liu, Li-Li; Li, Lie-Jun; Ge, Yi-Yuan; Lu, Min; Liao, Yu-Wei; Zeng, Guang-Kuan; Yao, Jin-Xiu; Situ, Jing-Wei; Yang, Li-Ye^*

来源：Frontiers in Genetics, 2023, 14: 1126099.

DOI：10.3389/fgene.2023.1126099

• thalassemia
• gene testing
• genotype
• China
• Guangdong Province

Background: Thalassemia presents a higher incidence in southern China. The objective of this study is to analyze the genotype distribution of thalassemia in Yangjiang, a western city of Guangdong Province in China.Methods: The genotypes of suspected cases with thalassemia were tested by PCR and reverse dot blot (RDB). Unidentified rare thalassemia genotypes of the samples were further ascertained by PCR and direct DNA sequencing.Results: Among 22467 suspected cases with thalassemia, 7658 cases were found with thalassemia genotypes using our PCR-RDB kit. Among these 7658 cases, 5313 cases were found with alpha-thalassemia (alpha-thal) alone, --(SEA)/alpha alpha was the most common genotype, accounting for 61.75% of alpha-thal genotypes, and the following mutations were found: alpha(3.7)/alpha alpha, -alpha(4.2)/alpha alpha, alpha(CS)alpha/alpha alpha, alpha(WS)alpha/alpha alpha, and alpha(QS)alpha/alpha alpha. A total of 2032 cases were found with beta-thalassemia (beta-thal) alone. beta(CD41-42)/beta(N), beta(IVS-II-654)/beta(N), and beta(-28)/beta(N) accounted for 80.9% of all beta-thal genotypes, and the following genotypes were found: beta(CD17)/beta(N), beta(CD71-72)/beta(N), and beta(E)/beta(N). Compound heterozygotes of beta-thal and beta-thalassemia homozygotes were identified in 11 and five cases, respectively, in this study. alpha-thal combined with beta-thal was identified in 313 cases, showing 57 genotype combinations of the coincidence of both Hb disorders; one extreme patient had a genotype of --(SEA)/alpha(WS)alpha and beta(CD41-42)/beta(-28). In addition, four rare alpha-mutations (--(THAI), HK alpha alpha, Hb Q-Thailand, and CD31 AGG > AAG) and six rare beta-mutations (CD39 CAG > TAG, IVS-II-2 (-T), -90(C > T), Chinese (G)gamma(+)(A gamma delta beta)0, CD104 (-G), and CD19 A > G) were also found in this study population.Conclusion: This study provided detailed genotypes of thalassemia in Yangjiang of western Guangdong Province in China and reflected the complexity of genotypes in this high-prevalence region, and this would be valuable for diagnosis and counseling for thalassemia in this area.

• 单位
  南方医科大学