Globin Gene Expression in Development

Developmental Expression of Globins - Multiple globin genes are expressed at different times in human development (Figure 7.22). In the early embryo, the hemoglobin genes expressed are those for the embryonic chains, and . As the fetus develops, these chains are replaced by and chains, and finally, at about the time of birth, the chains are replaced by chains. In addition, after birth a small amount of a chain is produced. By age six months, the infant will have almost all 2 2 (adult) hemoglobin. These developmental types of hemoglobin chain are slightly different, and each is coded for by a separate gene in the human genome.

See also: Evolution of Myoglobin/Hemoglobin Proteins

INTERNET LINKS:

> 1. Human Globin Genes

> 2. Globin Gene Server