Dominant β-Thalassemia Phenotype Caused by Hb Dieppe (: c.383A>G): Another Case Report.

Homozygous or compound heterozygous mutations of the β-globin gene lead to β-thalassemia (β-thal) major (β-TM) or β-thal intermedia (β-TI), whereas heterozygotes usually show microcytosis with negligible or no hemolysis. Certain missense mutations in exon 3, however, produce unstable globins causing a dominant β-thal phenotype or hemolytic anemia in heterozygotes. Here we report a mutation in exon 3 of the β-globin gene, which results in an unstable globin (Hb Dieppe) [β127(H5)Gln→Arg; : c.383A>G] with a dominant β-thal phenotype in two generations of a Chinese family. Physicians should be alerted to this mechanism of β-thal considering its relative rarity.