Given the task definition and input, reply with output. In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.

The originally embryonic gamma - globin locus duplicated and acquired a novel ( fetal ) pattern of expression in a defined time period ( 55 - 40 million years ago ) during primate phylogeny .
gamma - globin