A β-Thalassemia Trait with Two Mutations in Cis in a Chinese Family

A female of Chinese origin carried the codon 43 (G>T) (HBB: c.130G > T) and codons 71/72 (+A) (HBB: c.216_217insA) mutations of the β-globin gene in cis, identified during prenatal thalassemia screening. The double in cis mutations were inherited from her mother. Both of the two carriers behave as a traditional heterozygote for β-thalassemia (β-thal) with microcytosis and a high Hb A₂ level. This case report indicates that the possibility of multiple mutations in cis in a fetus with thalassemia trait has to be considered in a prenatal screening program.