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Comment on 2015 mRNA paper suggests data re-used in different contexts

(pubpeer.com)
159 points picture | 5 comments | 16 Jan 25 17:24 UTC | HN request time: 0s | source
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owlninja ◴[16 Jan 25 17:53 UTC] No.42728486[source]▶
I guess I'll bite - what am I looking at here?
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the__alchemist ◴[16 Jan 25 17:59 UTC] No.42728569[source]▶
An (agarose?) gel.

There are partial holes in at at one end. You insert a small amount of dyed DNA (etc) containing solution each. Apply an electrical potential across the gel. DNA gradually moves along. Smaller DNA fragments move faster. So, at a given time, you can coarsely measure fragment size of a given sample. Your absolute scale is given by "standards", aka "ladders" that have samples of multiple, known sizes.

The paper authors cheated (allegedly) by copy + pasting images of the gel. This is what was caught, so it implies they may have made up some or all results in this and other papers.

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1. shpongled ◴[16 Jan 25 18:07 UTC] No.42728684[source]▶
Close - this is a SDS-PAGE gel, and you run it using proteins. The bands in the first two rows are from a western blot (gel is transferred to a membrane), where you use antibodies against those specific proteins to detect them. The Pon S row is Ponceau S, a dye that non-specifically detects all proteins - so it's used as a loading control, to make sure that the same amount of total protein is loaded in each lane of the gel.
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2. doctorpangloss ◴[16 Jan 25 18:17 UTC] No.42728830[source]▶
Is it conceivable that the control was run once because the key result came from the same run? I can see a reviewer asking for it in all three figures, whereas they may drafted it only in one
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3. gus_massa ◴[16 Jan 25 18:53 UTC] No.42729312[source]▶
The horizontal label is fine, it says Pon S in all images. (I guess a wrong label would be obvious to detect for specialists.)

The problem are the vertical labels

In Figure 1e it says: "MT1+2", "MT2" and "MT1"

In Figure 3a it says: "5'-CR1", "CR2" and "3'-UTR"

In Figure 3b it says: "CR2", "CR3" and "CR4"

replies(1): >>42729370 #
4. ◴[16 Jan 25 18:58 UTC] No.42729370{3}[source]▶
5. shpongled ◴[16 Jan 25 19:41 UTC] No.42729906[source]▶
Based on the images, it is inconceivable that these are from the same run (see the dramatically different levels of TRF-S in each gel. One column/lane = one sample). This isn't something that would be included because of a reviewer - loading controls are required to meaningfully interpret the results (e.g. the data is useless without such a control).