In mouse embryos, the expression of Blimp1
has recently revealed a population of allocated
primordial germ cell precursors 24 hours earlier than
previously thought. Those ‘blimped’ precursors have
been shown to give rise, by mitotic division, to germ
cells only and no other cell lineages. Here, we try to
understand the events that lead to Blimp1 expression in
the primordial germ cell precursors and speculate on
what can be the role of Blimp1 during primordial germ
cell specification and gastrulation in the mouse. Finally,
we discuss the possible involvement of Blimp1 in the
two know modes of germ line segregation (epigenesis
and preformation)