A large-scale study involving over 28,000 women has demonstrated the effectiveness of next-generation sequencing (NGS) in identifying thalassemia carriers and preventing severe cases of the genetic blood disorder. Thalassemia, which can be fatal or require lifelong blood transfusions, was the focus of a pre-conception and early pregnancy screening initiative conducted across 29 ethnic groups.
Researchers found that 15.07% (4,226) of the women were carriers of thalassemia. Based on spousal screening results, couples were classified into high-risk (0.75%), low-risk (25.86%), and unknown-risk (69.19%) groups. Among high-risk couples, 59 foetuses were diagnosed with severe thalassemia, affirming the accuracy of the risk-based approach.
Of the 25,053 live births tracked beyond six months, only two severe thalassemia cases were recorded, both from unknown-risk couples. These cases were linked to late or incomplete screening and the presence of a rare variant, underscoring the importance of early and comprehensive testing.
The study also uncovered 64 rare thalassemia variants in 287 individuals, highlighting the disease’s genetic complexity. Migration patterns were found to influence carrier rates, with 93.9% of migrants to Chenzhou originating from high-prevalence regions in southern China.
Researchers concluded that NGS-based screening is a powerful tool in preventing severe thalassemia and called for ongoing efforts to implement early screening in regions with high or underestimated prevalence. The findings support broader genetic testing to address regional health disparities and reduce the burden of inherited disorders.
Reference
Zhang J et al. High efficiency of thalassemia prevention by next-generation sequencing: a real-world cohort study in two centers of China. J Genet Genomics. 2025;S1673-8527(25)00127-4.
