Hb Groene Hart [a119(H2)Pro -> Ser, CCT -> TCT (alpha 1)] has been reported in heterozygotes of Moroccan origin and also in association with the common -alpha(3.7) deletion. In all cases, the mutated protein was not detectable but was apparently associated with a mild a-thalassemia (thal) phenotype, presumably due to a modification of the a-globin chain domain that is recognized by the a hemoglobin stabilizing protein (AHSP). The present case of Hb Groene Hart homozygosity, confirms that the alpha-thal phenotype is associated with this a-globin chain. Hb Groene Hart must be quite frequent not only in Morocco but probably also among the northern African coastal population.
Giordano, P. C., Zweegman, S., Akkermans, N., Arkesteijn, S. G. J., Van Delft, P., Versteegh, F. G. A., ... Harteveld, C. L. (2007). The first case of Hb Groene Hart [α119(H2)Pro→Ser, CCT→TCT (α1)] homozygosity confirms that a thalassemia phenotype is associated with this abnormal hemoglobin variant. Hemoglobin, 31(2), 179-182. https://doi.org/10.1080/03630260701289490