New α2 globin chain variant with low oxygen affinity affecting the N‐terminal residue and leading to N‐acetylation [Hb Lyon‐Bron α 1(NA1)Val→Ac‐Ala]

Hemoglobin Lyon‐Bron was found in two members of a family of German ascent presenting with a moderate normocytic anemia. In this alpha2 globin variant, the N‐terminal valine of the chain was replaced by an alanine. Electrospray mass spectrometry of the α chain showed that, as normally, the initiator methionine was cleaved during globin processing but that the Nα‐terminal group was totally acetylated. This resulted in structural modifications of a region crucial for oxygen binding. As a consequence, hemoglobin Lyon‐Bron displayed both a reduced chloride effect and a decreased oxygen affinity, this last point explaining the apparent anemia. Am. J. Hematol. 69:214–218, 2002. © 2002 Wiley‐Liss, Inc.