TABLE 1.
Discrete stages in germ line development during mouse embryogenesis
| age (sex) | location and developmental stage of PGCs or gonocytes |
|---|---|
| e7.25 | PGCs at the base of the allantois |
| e8.75 – e9.25 | PGCs mostly in hindgut endoderm, non-migrating, mitotic (12–18 somite stage) |
| e10.25 - 10.5 | PGCs mostly in hindgut mesentery, migrating, mitotic (30–35 somite stage) |
| e11.5 | All PGCs in genital ridge, non-migrating, mitotic |
| e12.5 | gonadal differentiation initiates, PGCs mitotic |
| e13.5 (M) | testis discernible, PGCs differentiate into M-prospermatogonia, mitotic |
| e13.5 (F) | ovary discernible, PGCs differentiate into oogonia, some enter meiotic prophase = oocyte |
| e15.5 (M) | T1-prospermatogonia, in mitotic arrest |
| e15.5 (F) | few oogonia; mostly oocytes in meiotic prophase |