Welcome to mtthwgyd's page.
Contributor score: 5
School: Wright State
The egg shell is a ZP3-mediated process. It's the only thing between me and my treasure.

 +4  (nbme19#17)

This is what is known as a somatic mutation: a mutation that occurs in non-germline cells and, therefore, only effects daughter cells derived from the parent cell with the mutation. So, a mutation occurred in a differentiated parent cell that gave rise to a set of daughter cells (which, in this case, were destined to become retinal tissue).