Genetic predictions of life expectancy in southern Thai patients with β0-thalassemia/Hb E

The types of beta-thalassemia mutations, alpha-thalassemia interactions, and Hb F-associated SNPs have been described in association with variable disease phenotypes. This study aimed to determine the updated spectrum of beta-thalassemia mutations and evaluate the contribution of primary and secondary genetic modifiers and SNPs to disease severity, age at onset, and predicted life expectancy in southern Thai beta-thalassemia patients. A total of 181 beta-thalassemia patients were enrolled and 135 beta(0)-thalassemia/Hb E patients without alpha-thalassemia interactions were divided into three categories according to disease severity, age at onset, and predicted life expectancy. A total of 16 beta-thalassemia mutations were identified in this study, and the three most common beta-thalassemia mutations accounted for 61.4% of all mutations. It was also found that the XmnI polymorphism and rs2071348 were associated with age at onset and the predicted life expectancy. More than 82% of beta(0)-thalassemia/Hb E patients with CC genotype (XmnI) were 3 years old or younger at onset. Additionally, > 90% of the higher predicted life expectancy in beta(0)-thalassemia/Hb E patients had the T allele of XmnI. Therefore, genetic prediction for age at onset and life expectancy is beneficial and practical during prenatal diagnosis or newborn screening for better genetic counseling and optimal management.