Thalassemia and Hemoglobinopathies in an Ethnic Minority Group in Northern Vietnam

Abstract

This study assessed thalassemia and hemoglobinopathies in a group of the Tay ethnic minority. Participants included 289 women of reproductive-age who enrolled in a pilot screening program for thalassemia conducted at six communities of Thai Nguyen Province, northern Vietnam. Standard procedures including complete blood count (CBC), hemoglobin (Hb) and DNA analyses were performed for all samples. The prevalence of thalassemia in 289 Tay women was 15.6% (gene frequency 0.078) for α⁰-thalassemia (α⁰-thal), 10.0% (gene frequency 0.050) for α⁺-thal, 7.3% (gene frequency 0.036) for β-thalassemia (β-thal), 2.4% (gene frequency 0.012) for Hb Constant Spring [Hb CS; α142, Term→Gln, TAA>CAA (α2), HBA2: c.427T>C] and 1.7% (gene frequency 0.009) for Hb E [β26(B8)Glu→Lys, GAG>AAG; HBB: c.79G>A]. Further analysis of β-globin gene abnormalities identified four mutations including codons 41/42 (-TCTT) (HBB: c.126_129delCTTT), codon 17 (A>T) (HBB: c.52A>T), codons 71/72 (+A) (HBB: c.216_217insA), and -28 (A>G) (HBB: c.78A>G). The results hint at the remarkably high frequencies of severe forms of thalassemia that indicate a serious public health problem requiring further exploration, and most probably, also intervention within the country.

Keywords: Ethnic minority; Tay people; Vietnam; hemoglobinopathy; thalassemia.