Spectrin Jendouba: An αII/31 spectrin variant that is associated with elliptocytosis and carries a mutation distant from the dimer self-association site

Abstract

Spectrin Jendouba (αII/31) was found in a Tunisian family. In the heterozygous state, it is associated with asymptomatic elliptocytosis and a minimal defect in spectrin dimer self-association. On partial digestion of spectrin with trypsin, an abnormal cleavage appeared following Lys 788. Peptide and DNA sequencing indicated that the responsible mutation is α791 Asp → Glu (GAC → GAA). As in most α-spectrin variants associated with elliptocytosis, the change alters helix 3 of the proposed triple helical model of spectrin structure. Modified helix 3 in repeat 08 is the most distant from the N-terminus of α-spectrin in known variants associated with elliptocytosis. © 1992 by The American Society of Hematology.