Abstract
Hemoglobin (Hb) variant β141(H19)Leu→Val (HBB:c.424C>G), one of the two mutations defining Hb Kochi [the other one being β144(HC1)Lys-Tyr-His→0 (HBB:c.433A>T)], was found as an isolated mutation. In contrast to what was suggested for Hb Kochi, the new variant was not clinically silent. It displayed increased oxygen affinity and was associated with mild erythrocytosis.