The association of hemoglobin Knossos and hemoglobin Lepore in an Algerian patient

We report on a 54 years-old male patient from North-Eastern Algeria who combines two hemoglobin variants that are associated with thalassemia-like disorders: Hb Lepore and Knossos (beta 27 Ala----Ser) (1, 2). A beta-thalassemia intermedia picture gradually developed and finally required splenectomy at the age of 53. Total absence of Hb A2 indicated that the beta Knossos gene is most probably flanked with a delta(0)-thalassemia gene. No DNA deletion additional to the Lepore deletion was found. Hb F was elevated (12.3%) with 24% G gamma Hb F. In whole cells, Hb Knossos, representing 70% of total hemoglobin, displayed a decreased affinity for oxygen (P50 = 35 mm Hg), a fact presumably accounting for the relatively good tolerance of the condition.

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