First Report of a Case with Nondeletional Hb H Disease Caused by IVS-I-116 (A>G) of the α2-Globin Gene.

In this report, we describe a prenatal case with cardiomegaly and increased middle cerebral artery-peak systolic velocity (MCA-PSV) at 22 weeks' gestation. Fetal blood sampling revealed moderate anemia (Hb 7.4 g/dL) and increased Hb Bart's (γ4) level (28.2%), indicative of Hb H (ß4) disease. Molecular analysis of the family members revealed that the pregnant woman carried a heterozygous IVS-I-116 (A>G) (HBA2: c.96-2A>G) mutation of α2-globin gene, and the fetus was a compound heterozygote for IVS-I-116 and the Southeast Asian (- -SEA) deletion. This is the first reported case of nondeletional Hb H disease caused by the IVS-I-116 (A>G) mutation associated with fetal anemia identified by ultrasound.