Prevalence of hemoglobin E in Yunnan Province of Southwest China

Objective: The aim of this study was to investigate the prevalence of hemoglobin E (Hb E) as well as the hematological and the phenotypic features of Hb E-related disorders in Yunnan Province of Southwest China. Methods: A total of 30 908 individuals from more than 30 nationalities who were childbearing population were recruited in the present study. Hematological analysis including complete blood counts and quantification of Hb levels were performed by capillary electrophoresis. The identified carriers were further detected for molecular analysis by multiple gap-polymerase chain reactions (gap-PCR) and the PCR-reverse dot-blot. Results: Hematological results showed that 345 subjects were identified to be Hb E carriers (1.1%). The high incidence of carrying Hb E occurred in Achang (25.0%), Jingpo (23.5%), Dai (16.0%), and Lisu (13.6%). After performing molecular analysis in 201 carriers, 192 cases (95.5%) were heterozygous Hb E and 29 cases (14.4%) of Hb E were con-inherited with alpha-thal cases. The other beta-globin chain mutation included homozygous Hb E (three cases), beta(+)-thal/Hb E (one case) and beta(0)-thal/Hb E (five cases). Individuals in Dai had the most types of Hb E-related disorders. Severe anemia was observed in cases of beta(+)-thal/Hb E and beta(0)-thal/Hb E. Conclusions: There is a high prevalence of Hb E among Yunnan populations, especially in ethnic groups. In addition, the spectrums of Hb gene mutations would provide a support for the genetic counseling of Hb E-related disorders among Yunnan populations.