[Genetic screening and typing study of Thalassemia among ethnic Miao Group in Qianxinan area of China].

OBJECTIVE

To determine the carrier rate for thalassemia mutations in the ethnic Miao population of Qianxinan Prefecture.

METHODS

Ethnic Miao people suspected for thalassemia trait at the People's Hospital of Qianxinan Prefecture, Guizhou Province between November 2020 to September 2024 were selected as the study subjects. Gap-PCR technology combined with high-throughput sequencing was used to screen a total of 666 individuals. ArcMap v10.8.2 was used to create a spatial distribution map of thalassemia based on the screening results. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2016-01).

RESULTS

In total 254 positive cases were detected, with an overall positive rate of 38.14%. Among these, 173 cases were α-thalassemia (25.98%), 77 cases were β-thalassemia (11.56%), and 4 cases were αβ compound thalassemia (0.60%). The most common genotypes for α-thalassemia were αα/--SEA (positive rate = 10.06%, accounting for 38.73%), αα/-α3.7 (positive rate = 8.86%, accounting for 34.10%), and αCSα/αα (positive rate = 4.95%, accounting for 19.08%). The most common genotypes for β-thalassemia were β41/42(-TTCT)/βA (positive rate = 5.11%, accounting for 44.16%) and β17 (A>T)/βA(positive rate = 4.20%, accounting for 36.36%), with these two genotypes accounting for as much as 80.52%. The spatial distribution map indicated that the highest overall detection rate of thalassemia and α-thalassemia in the Miao population of Qianxinan Prefecture was in Xingyi City. The highest detection rate of β-thalassemia was in Zhenfeng County, and the highest detection rate of αβ compound thalassemia was in Wangmo County.

CONCLUSION

The detection rate of thalassemia among the ethnic Miaos from Qianxinan Prefecture is relatively high, which primarily consisted of α-thalassemia. Regular monitoring and educational outreach should be conducted.