Here is an example summary of this reading selection:

As the result of his daughter’s school project to create a family tree, Sir Paul Nurse, a Nobel Prize-winning geneticist, learned that both of his parents had been illegitimate. Years later, in the process of getting a green card to work in the United States, he also learned that the person he had been told was his sister was actually his mother. Together, these facts gave Nurse a new, more complex understanding of both his family and his genetic past.

Your summary will differ from this one in the way it is written, but it should include roughly the same information.