Young Again: How One Cell Turns Back Time

With every birth, cells begin anew. Scientists have found a biological mechanism underpinning the process in worms, which one day may be harnessed to restore our own damaged cells.

None of us was made from scratch. Every human being develops from the fusion of two cells, an egg and a sperm, that are the descendants of other cells. The lineage of cells that joins one generation to the next — called the germline — is, in a sense, immortal.

Biologists have puzzled over the resilience of the germline for 130 years, but the phenomenon is still deeply mysterious.

Carl Zimmer