ABSTRACT
Hb J-Meerut [HBA2: c.362C>A (or HBA1)] is a rare, stable, nonpathogenic a-globin gene variant that
peaks in the area between the P3 and A0 windows on high performance liquid chromatography
(HPLC). Few cases from different ethnic origins have been published but the majority were Asian
Indians. Coinheritance with other hemoglobin (Hb) variants are rarer and can change the Hb J-Meerut
phenotype making a diagnostic dilemma. In this study, we have reported 15 cases of Hb J-Meerut, discovered
during a wide spectrum study of a-globin chain variants in the UK. The diagnosis was confirmed
by forward and reverse DNA sequencing of the a1- and a2-globin genes. The average of the
Hb J-Meerut expression was 20.9% of total Hb and characterized by a retention time (RT) of 1.9 min.
(on average) on HPLC. The median of isoelectric focusing (IEF) was 5.6mm above Hb A. Among the 15
cases studied, one case coinherited the Hb E (HBB: c.79G>A) mutation in heterozygosity and another
case was associated with the Cap þ14 (C>G) [HBA1: c.-24C>G (or HBA2)] variant. We noticed that the
coinheritance of the Hb E mutation reduced the Hb J-Meerut expression with the formation of a hybrid
peak missed on the HPLC chromatograph. We also noticed an increased expression of Hb J-Meerut in
the case showing the coinheritance of the HBA2: c.-24C>G (or HBA1) variant.