Origami Assays Game
The following game uses a small design to illustrate how a pooled assay works. The game is played as follows:
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Choose either 1 or 2 numbers between 1 and 13. Write them down.
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Select which of the 10 wells contain your number.
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The decoder guesses what numbers you have by highlighting them in green . Near matches will be highlighted in gold.
Why is this impressive?
While this is a small example, stop to consider what it is doing. You are allowed to pick 0, 1, or 2 positive samples and the design is able to decode these all with just 10 assays. If we count them there are:
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0: 1 If you choose none, then this is 1 configuration.
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1: 13 If you choose one, then there are 13 configurations.
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2: 72 If you choose two, then there are 13*12/2=72 configurations.
This means that with just 10 assays we can uniquely identify any one of 86 possible configurations.
What about errors?
This small example also shows what happens if there is an assay failure. Try toggling one well to add in a false positive or false negative. You may find a few interesting outcomes:
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No green entries, just gold:
This outcome would suggest an assay error because there are positive results but those results are not explained by one or more of the samples being positive.
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Too many green entries:
If you choose 3 or 4 positive samples, the design becomes overloaded and starts to call many more samples as positive. These extra positive results are false positives.
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Positive assays not associated with green entries:
There are cases where we have green and gold entries, but some of the gold entries are not "explained away" by the other assay results. This state also indicates an assay error.