Table 1.

Some of the rules defined by the EMAGE curator

ID	Description
1	If a gene G, is expressed in a structure S, in Theiler Stage (T−1) and also in Stage (T+1), then G is very likely to be expressed in S in Stage T.
2	If the user, after examining the image of the experimental result, is confident that the gene G, is expressed in the structure S, then G is very likely to be expressed in S.
3	If a spatial annotation SA, suggests a gene G is expressed in structure S, and the curator has high confidence in SA, then we may have high confidence that G is expressed in S.
4	If a textual annotation TA, suggests a gene G is expressed in structure S and the curator has high confidence in TA, then we may have high confidence that G is expressed in S.
5	If a textual annotation TA, suggests a gene G is expressed in structure S and the curator has medium confidence in TA, then we may have medium confidence that G is expressed in S.
6	If the user does not trust the research team that conducted experiment E, then all spatial and textual annotations based on that experiment should have a low level of confidence.
7	If a spatial annotation SA and a textual annotation TA disagree, then always trust TA.
8	If two experiments disagree on whether, or not, a gene G is expressed in structure S and the user believes the experiments are examining different parts of S, then G is likely to be expressed in part of S.
9	If two experiments disagree on whether, or not, a gene G is expressed in structure S and the user believes the experiments are examining different parts of S, then G is likely to be not expressed in part of S.

Rules 1–7 are relatively straightforward. However, Rules 8 and 9 may require further explanation. They state that if two experiments are examining different parts of the same structure both results can be correct regardless of their conclusion. For example, consider two experiments on the human hand. The first experiment may find a particular gene expressed in the thumb, and the second conclude that the same gene is not expressed in the index finger. These experiments show that the gene is both expressed and not expressed in the hand.