Extended Data Figure 2. A coalesced proliferative SGZ does not form in the human DG; additional marker expression.

a, Toluidine blue counterstained semithin sections of the human GCL from fetal to adult ages. Note that a discrete cellular layer does not form next to the GCL and the small dark cells characteristic of SGZ precursors are not present (compare to Extended Fig. 9b in the macaque). b, BLBP+ cells are distributed broadly in the DG from birth to one year, many of these cells have an elongated morphology (see insets) and some co-express Ki67 (arrows) at birth and one month. By 7 years and in adults, most BLBP is present in the ML in stellate protoplasmic astrocytes. c, DCX+Ki67+ cells in the GCL are rare at 17 GW (orthogonal views, inset) but were abundant in the GE at the same age (not shown). DCX+Ki67+ cells were absent in the GCL from 22 GW to 55 years. Scale bars: 100 μm (a–c), 10μm (a–c, insets).