Codon 104(-G), a dominant beta0-thalassemia-like phenotype in a German Caucasian family is associated with mild chronic hemolytic anemia but influenced in severity by co-inherited genetic factors.

Codon 104(-G), a heterozygous frameshift mutation in exon 2 of HBB, resulted in a dominantly inherited beta0-phenotype with mild anemia in a German kindred, and thalassemia intermedia in the index patient. A co-inherited a gene triplication, long-term transfusion therapy, and ineffective erythropoiesis were confounding factors.