‘Silent’ β-thalassaemia caused by a ‘silent’ β-chain mutant: the pathogenesis of a syndrome of thalassaemia intermedia

Abstract
In a Greek family 3 cases of .beta.-thalassemia intermedia were diagnosed as resulting from the interaction of a typical high HbA2-.beta.-thalassemia with an atypical (silent) .beta.-thalassemia gene. Following electrophoresis of globins on an acid-urea-Triton-acrylamide system, an otherwise silent .beta.-like variant was revealed in the carriers of the atypical thalassemia gene and in the intermediates; it amounted to 33% of the non-.alpha. chains in the former and to .apprx. 75% in the latter. The provisional name Hb Knossos is suggested for this abnormality.