The following will be published in the issue of Developmental Neuroscience following this paper:

Since the publication of our manuscript "Loss of Notch Activity in the
Developing Central Nervous System Leads to Increased Cell Death" in your
journal, we have discovered that the transgenic line Dlx5/6-Cre-IRES-EGFP
displays elevated levels of cell death in the forebrain during embryogenesis
(E12-E16) compared to control animals that lack this transgene. We used this
Cre transgenic line to remove the Notch1 gene in the vental forebrain and
published the observation that cell death was increased in the Dlx5/6-Cre;
Notch1 conditional knockouts (Fig. 4C). At this time we do not know whether
the Dlx5/6-Cre; Notch1 conditional knockouts have significantly more cell death
than the Dlx5/6-Cre transgenics alone. However, it is clear that removing both
the Notch1 and Notch3 genes does lead to dramatically increased cell death
compared to the Dlx5/6-Cre; Notch1 single conditional knockout as well as the
Dlx5/6-Cre transgenic.