Why do we age? We have the same genes throughout our lives. These genes encode all stages of life. In babies, genes for growth and learning are turned on. In puberty, genes for sexual development and desire are turned on. In old age, genes for inflammation and auto-immunity and programmed cell death are turned on. This is all done through removable markers on the DNA.
The way to make an old person young would be to change the markers on DNA in every cell in the body, reverting back to what they were in youth. But normally, changes in these markers progress in one direction throughout life. The only exception is making new life. In egg and sperm cells, the markers are reset to zero.
Is there a way to do a "partial reset", not turning every cell into an egg cell, but making it younger? Vittorio Sebastiano at Stanford wants to find out.