When does the synthesis of Hemoglobin A2 typically begin?

The synthesis of Hemoglobin A2 typically begins in the mid-second trimester of fetal development. Hemoglobin A2 is one of the various types of hemoglobin produced by the body, playing a smaller role compared to Hemoglobin A, which is the primary form of hemoglobin found in adults.

Throughout the gestational period, different types of hemoglobins are produced at various stages. Initially, embryonic hemoglobins are predominant in the early stages of development, but fetal hemoglobin gradually takes over. Hemoglobin A2 begins to be synthesized around the mid-second trimester as the fetus develops and its need for oxygen increases. It will continue to be produced and eventually comprises a small percentage of total hemoglobin in healthy individuals after birth.

Understanding the timeline of hemoglobin synthesis is crucial for recognizing normal fetal development and the conditions that may arise from abnormal hemoglobin production.