Background: Hemoglobin J is one of the fast hemoglobin that has a more negative charge due to β77His→Asp substitution. Acquisition of this hemoglobin is not associated with any specific clinical sign, but the combination of this hemoglobinopathy with beta-thalassemia and other hemoglobinopathies can cause challenges.
Case presentation: In this article, two cases with hemoglobin J are introduced; the first patient for premarital testing and the other for his fatigue. The hemoglobin electrophoresis was done by Sebia capillary zone electrophoresis and Hb J as heterozygote and homozygote were determined.
Conclusion: It must be noted that although this hemoglobinopathy is not related to any problem alone but could be confusing in combination with other hemoglobinopathies or thalassemia. In this paper, these two cases are introduced and an attempt was made to investigate the importance of molecular follow-up.
Keywords: Fast hemoglobin; Hemoglobin J; Hemoglobinopathy; Molecular diagnosis; Thalassemia.