Molecular Characterization of α- and β-Thalassemia Among Children Less Than 18 Years Old in Guizhou, China

Abstract

Background: Thalassemia is an inherited hemolytic disease, the complications and sequelae of which have posed a huge impact on both patients and society. But limited studies have investigated the molecular characterization of α- and β-thalassemia in children from Guizhou, China.

Methods: Between January 2019 and December 2022, a total of 3301 children, aged 6 months to 18 years, suspected of having thalassemia underwent molecular analysis.

Results: Out of the total sample, 824 (25%) children were found to carry thalassemia mutations. The carrier rates of α-thalassemia, β-thalassemia, and α + β-thalassemia were determined as 8.1%, 15.6%, and 1.3%, respectively. Approximately 96.5% of the α-thalassemia gene mutations were --SEA (51%), αα^CS (20.9%), -α^3.7 (19.6%), and -α^4.2 (5.0%). The most prevalent mutations of β-thalassemia were β^CD17(A>T) (41.5%), β^{CD41-42(-TTCT)} (37.7%), and β^{IVS-II-654(C>T)} (11.3%). Additionally, we identified rare cases, including one case with αα^{Hb Nunobiki}/αα, two cases with triplicated α-thalassemia (one case with ααα/ααα and β^CD41-42/β^N and the other with ααα^-3.7/αα and βE ^CD26/β^N), and also one case with α ^Q-Thailandα/-α^4.2 and β^CD41-42/β^N.

Conclusions: Our study findings provide important insights into the heterogeneity of thalassemia carrier rates and molecular profiles among children in the Guizhou region. The findings support the development of prevention strategies to reduce the incidence of severe thalassemia in the future.

Keywords: carrier rate; children; molecular analysis; molecular characterization; thalassemia.