Referee 1's review:
In this revised manuscript, the only new data are the real time RT-PCR. These data are severely flawed by virtue of the fact that they provide only expression relative to baseline and no comparison to islets. There have been many papers in which claims have been made for beta-cell differentiation from a completely unrelated cell type. The most common problem in those papers is discordance between the level of insulin gene expression, which is generally very low, and the amount of protein, which is claimed to be very high. This problem appears to exist in the current manuscript.
Baseline expression for insulin mRNA in their cells should be essentially zero. Thus, what does it mean for there to be a 6-fold increase? The same comment applies to the other genes assayed as well.
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N.B. These are the general comments made by the reviewer when reviewing this paper in light of which the manuscript was revised. Specific points addressed during revision of the paper are not shown.
