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.

This region is located within the 920 bp fragment located 210 bp upstream from the coding region and this fragment represents a possible novel DNA region , which plays a role in the stage - and tissue - specific expression of immunoglobulin genes .
immunoglobulin genes