ABSTRACT
Objectives
To explore the application of third-generation sequencing (TGS) for genetic diagnosis and prenatal genetic screening of thalassemia genes.
Methods
Two groups of subjects were enrolled in this study. The first group included 176 subjects with positive hematological phenotypes for thalassemia. Thalassemia-associated genes were detected simultaneously in each sample using both the PacBio TGS platform based on single-molecule real-time (SMRT) technology and the conventional PCR-reverse dot blot (PCR-RDB). Sanger sequencing was used for validation when results were discordant between the two methods. The second group included 53 couples with at least one partner having a positive thalassemia hematological phenotype, and they were screened for homotypic thalassemia variants by TGS, and the risk of pregnancies with babies presenting with severe thalassemia, was assessed.
Results
Of the 176 subjects, 175 had concordant genotypes between the two methods, including 63 normal subjects and 112 α- and/or β-thalassemia gene carriers, with a concordance rate of 99.43%. TGS detected a rare β-thalassemia gene variant −50 (G > A) that was not detected by conventional PCR-RDB. TGS identified seven of the 53 couples as homotypic thalassemia gene carriers, five of whom were at risk of pregnancies with severe thalassemia.
Conclusion
TGS could effectively detect common and rare thalassemia variants with high accuracy and efficiency. This approach would be suitable for prenatal thalassemia genetic screening in areas with high incidence of thalassemia.
Acknowledgements
The authors thank tall individuals for their participation in this study. The authors would like to express their gratitude to EditSprings (https://www.editsprings.cn) for the expert linguistic services provided.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Ethics statement
Informed consent was obtained according to the Declaration of Helsinki.
Data availability statement
All data in this study are shown in the figures and tables.