Sperm have a vital role in the continuity of a species by contributing genetic information to
the next generation. Production of these specialized gametes in numbers sufficient to confer
normal fertility occurs via cycling of the spermatogenic lineage, a process referred to as
spermatogenesis. Continuity relies on the activities of a self-renewing reservoir of
spermatogonial stem cells (SSCs) from which progenitors will arise that transiently amplify in
number before committing to a pathway of terminal differentiation. A primary population of …