Embryonic hemoglobin

The embryonic hemoglobin is a tetramer, which is produced during the mesoblastic period ( from the first week of pregnancy up to the end ) in the yolk sac. The protein is generally ε as hemoglobin or HbE respectively.

Chromosome errors can lead to a delay when switching from embryonic hemoglobin.

Subtypes include Gower 1, Gower 2, and Portland 2