Katherine Unger Baillie for Penn Today: “Unlike women, who are born with all the eggs they’ll ever have, men can continue to produce sperm throughout their adult lives. To do so, they require a constant renewal of spermatogonial stem cells, which give rise to sperm.
“This reinvigoration of stem cells depends on a newly characterized stem cell self-renewal factor called DOT1L, according to research by Jeremy Wang of the University of Pennsylvania School of Veterinary Medicine and colleagues. When mice lack DOT1L, the team showed, they fail to maintain spermatogonial stem cells, and thus, lack the ability to continuously produce sperm.”